Database Develop

MMC Plus and SD 4Gb - slow write speed

Here is a problem... I've tested 4Gb SD card's FAT16 write speed using XDA IIi. And it is 2 times slower than one on 2Gb SD card(both Transcend, 150x). Nearly 630kb/s(2Gb) and 375kb/s(4Gb).
So, speed is unacceptable.
Will 4Gb MMC solve this speed problem?

Hi
You need to reformat you SD4Gb in Fat32. I had same problem like you with MMC+ 4Go and SD 4Go 150x, both from transcend. I reformated in FAT32 and they are more quicker.
Try it and ket me know.
You can use Pocket Mechanic from Anton Tomov which is a very good software.
Cheers

Hmm... Same benchmark gives me even slower result with FAT32... What cluster size are you using?
Best results achived with FAT16 64Kb cluster... Using SKTools for benchmarking.

Sectors per cluster:64
Bytes per sector: 512
Cluster Size is 64x512 = 32768
Hope it helps

A Closer Look At MicroSD and Reader Speed

This thread is about testing MicroSD cards using Crystal Disk Mark to determine actual card read/write speed.
This thread is a supplemental thread to: SD Strange-results - or - How I learned to love CM7 on SD
The above linked thread is pretty much a pre-requisite for this thread. Read that one first, then come back here.
This thread is designed specifically to be a supplement to that thread, and expand on something without confusing the information presented in the other thread.
Further reading should also include Runing OS from SD. Re: SD Strange-results - or - How I learned to love CM7 on SD. This thread approaches the issue from another angle, and these 3 threads paint a more comprehensive picture of this situation then any 1 individually. I think that as this one develops it'll benefit us greatly on this subject.
WARNING: Long read.
Thread Focus: Accuracy & Reliability
Regarding: Crystal Disk Mark (v. 3.0.1) MicroSD card benchmark test results. Computer state and physical hardware used.
Thread Navigation:
Post 01 - Introduction, what this thread is about.
Post 02 - Benchmark Software, Memory Specifications.
Post 03 - Hardware: Computer, MicroSD cards, and Adapters/Readers.
Post 04 - Step by Step Procedures.
Post 05 - Results: Initial Test
Post 06 - Results: Test 2
Post 07 - Results: Averages
Post 08 - Results: Averages: SanDisk
Post 09 - Review/Questions/Notes.
Post 10 - Reserved
(Link to single post, reference purposes. Post 01 to reload whole thread.)
Updates:
-06 / 11 / 11 : Test 2 Results uploaded. I'm still on vacation, so over the next few days i'll be editing this thread a bit to clarify some things, tidy links and what-not, but the data is there now. Not the best environment at the moment to do that. Results in Post 06.
--------------------------------------------------------
This thread details the testing procedures and results of a test on MicroSD cards and the adapters used.
Some questions that helped spawn this thread:
- Does it make a difference whether the benchmark is run through a MicroSD to SD card adapter, USB card reader, etc...
- Is the test reliable? How much do the results vary from test to test? What's the margin for error in a result?
- How much does the computer environment affect the test?
Goals:
01 - Total of 5 full tests, testing each card in each adapter on a fresh PC install.
02 - To average all 5 results from each test and get a more reliable card rating.
03 - To design a test that can be duplicated as exactly as possible.
04 - Determine how reliable the test results are when repeated. Discover % margin for error.
05 - To start to discover which method of input to pc is best, and determine how test results may vary between them.
06 - To compare my new test results to my old from a more normal user environment.
07 - To provide a baseline metric for others to build on, or at the very least refer to.
A considerable amount of effort was put into identifying, isolating and eliminating as many variables as possible. Great care was taken to ensure that the testing environment (computer) was as identical as possible from Test to Test and benchmark result to benchmark result. Same with the test objects. (MicroSd cards)
I can only test what I have. Over the next few weeks i'll be picking up some adapters/readers and a few more cards, specifically to round out the test data.
Furthermore, I had to really crunch it in to get all the test data done. Emphasis was on getting the data, not sorting it, so only the most basic averages have been done so far. There is a lot more computation on the way.
With the data itself gathered and organized, though, others can calculate whatever they want if I haven't yet, or haven't thought of. All of the original results from the program are included.
The spreadsheets are not all pretty with colors and such, but they are clean, organized and formatted just enough to manage the data. Once it's all sorted and computed, i'll work on making it look pretty.
This was a good run using what I had, but i'd like to see first-hand results from at least two of each adapter or reader used. I came this far, so i'll go at least that much further right away.
I will start actively paying attention to memory card sales at retail stores. Different stuff is on sale all the time, sometimes for pretty cheap. As far as testing goes, anything not already benchmarked is a candidate. Stuff that benchmarked well already is also a candidate.
Accuracy and reliability are the two guiding aims of this project. Any suggestions on improving my test procedure in that direction?
I am on the road a lot for work, and there are times where I may not have internet access for a week or so. If I haven't been around in a couple of weeks, i'm not gone, just absent. Don't want anyone to think I abandoned this.
I can work on charts and stuff in my random offline free time, so when I get the chance I can upload what I have.

Testing Software
Thread Navigation:
Post 01 - Introduction, what this thread is about.
Post 02 - Benchmark Software, Memory Specifications.
Post 03 - Hardware: Computer, MicroSD cards, and Adapters/Readers.
Post 04 - Step by Step Procedures.
Post 05 - Results: Initial Test
Post 06 - Results: Test 2
Post 07 - Results: Averages
Post 08 - Results: Averages: SanDisk
Post 09 - Review/Questions/Notes.
Post 10 - Reserved
(Link to single post, reference purposes. Post 01 to reload whole thread.)
Testing Software:
Crystal Disk Mark version 3.0.1 (Current version at time of initial testing.)
Preferred test is the 50MB test run 5 times, otherwise represented as 5x50MB.
Some people have mentioned not being able to run other tests with a higher data value, and most people run the 5x50MB test. For a more global level of comparable test results, this is what we should use.
Since the results given by that test are each the average of 5 numbers (5x part of it's name), I also chose to run each test 5 times and average the results.
This is also the basis I am basing "done" versus "yet to be done" on. I want to have test data from each combination available of memory card and adapter/reader, 5 tests on each.
This should yield:
- A solid benchmark for each memory card.
- A solid comparison for each adapter/reader used.
Memory Specifications, Information:
? at this time, more to come.
Feel free to post information in this thread that should end up here. I'll edit in a quote or cite your post for the info when I get a chance.
Update 6/2/11: psychoace post#16 - Voltage

Hardware Used in Testing
Thread Navigation:
Post 01 - Introduction, what this thread is about.
Post 02 - Benchmark Software, Memory Specifications.
Post 03 - Hardware: Computer, MicroSD cards, and Adapters/Readers.
Post 04 - Step by Step Procedures.
Post 05 - Results: Initial Test
Post 06 - Results: Test 2
Post 07 - Results: Averages
Post 08 - Results: Averages: SanDisk
Post 09 - Review/Questions/Notes.
Post 10 - Reserved
(Link to single post, reference purposes. Post 01 to reload whole thread.)
Machine Used:
HP Probook 4510s (laptop 1.5 years old, purchased new)
-Intel Core 2 duo CPU T6570 @ 2.10GHZ
-2 Gigs of Ram
-USB port is USB 2.0
-Onboard SDcard slot. (integrated card reader)
- First line of each card/adapter/reader listed starts with "Tag:". This is the identifier used to reference it throughout my test data and results.
Cards tested:
Code:
Tag: Sandisk C2 16G(1)
Brand, Size, Class - Sandisk MicroSDHC, 16 Gig, Class 2
Accessories - None
Tag: Sandisk C4 8G(1)
Brand, Size, Class - Sandisk MicroSDHC,8 Gig, Class 4
Accessories - SD card adapter
SDSDQ-8192-A11M
Tag: Sandisk C4 8G(2)
Brand, Size, Class - Sandisk MicroSDHC, 8 Gig, Class 4
Accessories - None
Tag: Sandisk C4 8G(3)
Brand, Size, Class - Sandisk MicroSDHC, 8 Gig, Class 4
Accessories - None
SDSDQ-008G-A11M
Tag: Sandisk C4 8G(4)
Brand, Size, Class - Sandisk MicroSDHC, 8 Gig, Class 4
Accessories - None
SDSDQ-008G-A11M
Tag: Sandisk C4 8G(5)
Brand, Size, Class - Sandisk MicroSDHC, 8 Gig, Class 4
Accessories - None
SDSDQ-008G-A11M
Tag: PNY C10 8G(1)
Brand, Size, Class - PNY MicroSDHC, 8 Gig, Class 10
[COLOR="Red"]Accessories - SD card adapter ((Broken))[/COLOR]
Tag: DaneElec C4 4G(1)
Brand, Size, Class - Dane/Elec MicroSDHC, 4 Gig, Class 4
Accessories - SD card adapter
[COLOR="red"]Accessories - USB MicroSD card reader ((Broken))[/COLOR]
Tag: PNY 2G(1)
Brand, Size, Class - PNY MicroSD,2 Gig, Un-classed
[COLOR="red"]Accessories - SD card adapter ((Broken))[/COLOR]
Adapters tested:
Code:
Tag: Sandisk SD(1)
SanDisk MicroSD, MicroSDHC to SD Adapter.
Tag: n/a
[COLOR="Red"]PNY MicroSD Adapter ((Broken))[/COLOR]
Tag: n/a
[COLOR="red"]PNY MicroSD Adapter ((Broken))[/COLOR]
Tag: DaneElec SD(1)
Dane-Elec MicroSD Adapter
SanDisk USB MicroSD Adapter - SDDRK-121-A11M
SanDisk USB MicroSD Adapter - SDDRK-121-A11M
SanDisk USB MicroSD Adapter - SDDRK-121-A11M
SanDisk USB MicroSD Adapter - SDDRK-121-A11M
SanDisk USB MicroSD Adapter - SDDRK-121-A11M
USB Readers Tested:
Code:
Tag: DaneElec USB(1)
[COLOR="red"]Dane-Elec USB MicroSD Reader ((Broken))[/COLOR]
SanDisk USB MicroSD Reader - SDDRK-121-A11M
SanDisk USB MicroSD Reader - SDDRK-121-A11M
SanDisk USB MicroSD Reader - SDDRK-121-A11M
SanDisk USB MicroSD Reader - SDDRK-121-A11M
SanDisk USB MicroSD Reader - SDDRK-121-A11M

Step by Step Procedures
Thread Navigation:
Post 01 - Introduction, what this thread is about.
Post 02 - Benchmark Software, Memory Specifications.
Post 03 - Hardware: Computer, MicroSD cards, and Adapters/Readers.
Post 04 - Step by Step Procedures.
Post 05 - Results: Initial Test
Post 06 - Results: Test 2
Post 07 - Results: Averages
Post 08 - Results: Averages: SanDisk
Post 09 - Review/Questions/Notes.
Post 10 - Reserved
(Link to single post, reference purposes. Post 01 to reload whole thread.)
Topics in this post: (post contents)
-Computer Preparation Procedure
-Card Preparation Procedure
-Run Test Procedure
-Result Naming/Organization.
-Result Processing.
Computer Environment, Quick Overview:
- Windows XP Service Pack 3, fresh format and install.
- Installed on drive C.
- Crystal Disk Mark (v. 3.0.1) is the only program installed.
- A few settings changed in XP to optimize for testing (see Computer Prep Procedure)
- Networking disabled at the hardware level. Computer never networked during the testing.
- Wireless also disabled by toggle switch on the front of the laptop.
- No open networks within WiFi range of test location.
* - Always re-installed fresh, starting with the format of laptop drive C:, before starting a new test.
Computer Preparation Procedure:
01 - Boot to WinXP install CD.
02 - Format drive C: using the NTFS file system, full format. (NOT quick) Install Windows XP.
** - Choose 'Not Right Now' when prompted about automatic updates during install.
03 - Copy HP 4510s drivers folder from cd, install all system drivers. Reboot after each one.
04 - Copy Service Pack 3 Install.exe (redistributable) from cd, install SP3. (reboot)
** - Choose 'Not Right Now' when prompted about automatic updates on reboot.
## - Edit WinXP Settings:
05 +- Go to "Device Manager" and disable: Wireless Nic, Wired Nic, Modem, Webcam.
06 +- Go to "System Properties, Advanced Tab, Performance Settings": "Adjust for best performance"
07 +- Go to "System Properties, System Restore Tab": Turn off for all drives.
08 +- Go to "Power Options, Power Schemes Tab": Set "plugged in" to "Never" for all.
09 +- Go to "Display, Screen Saver Tab": Set to "None".
10 - Reboot.
11 - Install CrystalDiskMark (v. 3.0.1) from CD. (Say no to promo offer during setup)
12 - Delete: Copied Drivers install folder, SP3 install exe.
13 - Reboot
14 - Run "Disk Cleanup". All boxes checked.
15 - Run "Disk Defragmenter" on drive C:
16 - Reboot.
* - Laptop prepped and ready, environment as sterile as possible.
## - Next Procedure: Card Preparation.
Notes on the Computer Preparation Procedure:
- Chose to install drivers, etc... from CD to avoid attaching any usb devices not used in testing. Limits variables.
- Drivers always installed in the same order, and logically so (first chipset, second video, third audio, etc.. down the line of importance)
- Reboot = Save. No install is finished until the computer reboots. Always finish one task before moving on when accuracy is important.
- Reboot = Fresh Start. All RAM is cleared on reboot. Any processes, cached results, ghosts of previous benchmark results, or whatever are cleared from RAM upon reboot. Also ensures that the same amount of RAM is available for each individual benchmark, as much as can be.
- Average reboot time is 43 seconds, from clicking "reboot" until the system is loaded and ready to use. (Averaged of 50 recorded reboots in this exact setup.)
- This 16 step procedure should ensure that each test is run in the same operating environment, as much as is possible.
Card Preparation Procedure:
01 - Boot Nook without MicroSD card into it's stock, 1.2 configuration.
02 - Insert MicroSD card into Nook.
03 - Go to "Device Info, SD Card": Format card. (or unmount and format, if necessary)
04 - Unmount and remove MicroSD card.
05 - Using a MicroSD-to-SD Adapter, insert into laptop.
06 - Go to "My Computer": right-click on and format the MicroSD card. (full format, not quick. Default options, no label (leave it blank))
07 - Go to "Safely Remove Hardware": Safely Remove MicroSd Card.
08 - Reboot.
09 - Repeat for each card being tested.
10 - Reboot computer when finished.
* - All MicroSD cards ready, prepped as identically as possible.
## - Next Procedure: Run Test
Notes on the Card Preparation Procedure:
?- Why format in the Nook first? Isn't that just extra... (card wear, time, an extra step, etc...)
+- All noted and weighed against one heavy fact: Windows XP is lazy. It tries to cut corners, and that's it's job...all in the name of serving you more quickly. Faster to load from cache then generate new, etc...
+- Making XP format the card coming from the Nook, it has to actually do something to format it. The result is not going to look just like it did before it started. This ensures XP formats the card, and also provides windows with the same thing to format every time. (As much as possible.)
+- 'Extra step' taken for variable control. Formatting the same information on each card is an attempt to ensure each card is programmed as identically as possible. ...what you start with can effect what you end up with...
- Make sure to use the same MicroSD to SD Adapter for each MicroSD card formatted.
- Using the same MicroSD to SD adapter for Card Preparation is also about variable control.
Run Test Procedure:
Pre 1 - Perform Install Procedure on the computer.
Pre 2 - Perform card preparation procedure on each MicroSD card to be used during the test.
Pre 3 - One at a time, insert any USB devices to be used in the test, with no MicroSD card in the device. This allows Windows to recognize and install any drivers necessary. Make sure to "Safely Remove" each device, and before rebooting. Reboot when finished.
01 - Power on computer, Reboot if already on. Wait until fully loaded and ready before next step.
02 - Insert MicroSD card into Adapter/Reader.
03 - Insert Adapter/Reader into computer.
04 - Run Crystal Disk Mark. Make sure to select the right type of test to run on the MicroSD card. (example: 5 x 50MB)
05 - Save results to Notepad file.
06 - Go to "Safely Remove Hardware": Safely Remove Adapter/Reader.
07 - Physically remove Adapter/Reader from computer.
08 - Physically remove MicroSD card from Adapter/Reader
09 - Reboot computer.
Choose:
10a - Repeat steps 2 through 9 for next Adapter/Reader using the same MicroSD card.
10b - If no next Adapter/Reader, repeat steps 2 through 9 on the next MicroSD card. (Make sure to test Adapters/Readers in the same order as the previous card.)
10c - If no next Adapter/Reader or MicroSD Card, Proceed to step 11.
11 - Insert USB thumb drive, copy notepad benchmark files from the computer.
* - End of Test.
* - Compile results.
Notes on the Run Test Procedure:
- Always "Safely Remove" Adapter/Reader from computer. Never just pull it out. DO NOT 'eject' from "My Computer" window.
- Always "Safely Remove" before a reboot, so Windows isn't expecting hardware that may not be there the next time it's powered on. (..and it won't effect the ram for the next benchmark.)(Start fresh, each time.)
- Make sure to always reboot when called for. Single greatest measure of variable control during testing. Prevents any contamination of RAM from the last benchmark, or anything else.
- Make sure to always use the same physical USB port on the computer for all benchmarks run. Uses the same physical circuitry pathway for each result, more variable control.
- Do not insert USB thumb drive, or any other devices, into the computer until the last Crystal Disk Mark result is recorded from the Test. Simply plugging it into the computer introduces irrelevant information to the computer environment, possibly contaminating benchmark results. Once all benchmarks have been recorded for that Test, it doesn't matter any more since the computer itself will be reformatted before the next test.
Result Naming/Organization:
- From step "02" to "09" represents one segment of a test.
- Each segment produces a Crystal Disk Mark result.
- Seperate segments are identified by number (Segment 1, Segment 2, etc...)
- Each segment is labelled afterwards, name edited in to replace the link in the generated result.
- Each segment is labelled with the name written backwards, so it's name starts with itself. (see example below)
- From step "Pre 1" to "11" represents one whole test.
- Seperate tests are identified by number (Test 1, Test 2, etc...)
- Each test is run on a fresh format/install of Windows XP on the computer.
- Each test starts with the MicroSD cards formatted the same.
- Neither the computer or the MicroSD cards are formatted again during the Test.
- Multiple tests are grouped by series.
- Seperate series are identified by name (Series:Initial, Series:Sandisk, etc...)
- A series represents one complete benchmark that includes the results from all MicroSD cards and Adapters/Readers tested.
- Multiple series are grouped under the identifier "(date)Benchmark: (test type)"
- (date) is the completion date of the Benchmark.
- (test type) is the type of test run by Crystal Disk Mark.
Naming convention examples:
Correctly written full name. Order and style used on charts of results. Individual results stay together when sorting on the computer.
1 - Example full name of an individual Crystal Disk Mark result from today, the date of this posting:
05.29.2011Benchmark:5x50MB, Series:Initial, Test 1, Segment 1
(result)
2 - Example full name of an individual Crystal Disk Mark result from February 1st of next year:
02.01.2012Benchmark:5x50MB, SeriesNY8GIG, Test 3, Segment 4
(result)
On the individual results themselves, generated by Crystal Disk Mark, I wrote the names backwards, declaring the record itself and working up to what test it was a part of.
Reason being: When you are browsing the source records, knowing the segment of the test is more important information then what test it was a part of. It makes it much easier and quicker to browse the results from the human perspective.
1 - Example of the label as it would appear on the result itself, from 1 above:
Segment 1 of Test 1, Series:Initial
(result)
2 - Example of the label as it would appear on the result itself, from 2 above:
Segment 4 of Test 3, SeriesNY8GIG
(result)
Don't worry if it sounds confusing, the next post has the test results in it. Dive into the numbers and it'll all make sense. You can always refer back here later.
It'll make more sense the first time I update the results with new data.
Results Processing:
- The Crystal Disk Mark result is copied to a notepad file. In the top of the result, the link is replaced with the name of the result in testing.
- Notepad results are saved by MicroSD card. Name = Tag heading in spreadsheet.
- All the test data was copied from the notepad files into an Excel spreadsheet. I checked for errors, but that doesn't mean there aren't any. The original notepad results from Crystal Disk Mark are included, along with the spreadsheets in case anyone wants to look.
- Post an error if you find it so I can correct it - Thanks!
- I let Excel do all of my computations. When it averages beyond 3 decimal places deep I truncated the results before taking the next average. I did not round anything. The data is there anyone wants that information, I don't think it's the right way for the test... educate me if i'm wrong.
- All Excel Spreadsheets are saved with the cursor in cell A1 of each sheet used.
- When posting a test, post starts with test details then presents results in code blocks by memory card.
- Code blocks are further organized with the read and write speeds of each adapter/reader listed under the cards average.
- Zip file of test folder with notepad/spreadsheet included with posting of test.

05.27.2011 Benchmark 5X50MB Initial Test Results
Thread Navigation:
Post 01 - Introduction, what this thread is about.
Post 02 - Benchmark Software, Memory Specifications.
Post 03 - Hardware: Computer, MicroSD cards, and Adapters/Readers.
Post 04 - Step by Step Procedures.
Post 05 - Results: Initial Test
Post 06 - Results: Test 2
Post 07 - Results: Averages
Post 08 - Results: Averages: SanDisk
Post 09 - Review/Questions/Notes.
Post 10 - Reserved
(Link to single post, reference purposes. Post 01 to reload whole thread.)
05.27.2011 Benchmark 5X50MB Initial Test Results
87 out of 90 tests run.
3 tests unable to be completed due to hardware failure.
I started this test with 4 MicroSD to SD card adapters and one USB MicroSD card reader.
Right away the 2 PNY MicroSD to SD adapters did not work. One was years old, the other brand new with the PNY C10 card I got. I know the old one used to work.
Every memory card I have works in every other adapter. Those two won't read any card. I am confused, but proceed with the test anyway. Now testing with 2 MicroSD to SD adapters and one USB adapter.
The USB adapter quit on me right at the last 3 cards of the last test. I could not get it to read any cards, it just up and stopped working with no warning.
The 3 Sandisk cards have all 5 tests on each reader. The two PNY and one DaneElec card are missing the data from test 5 on the USB reader.
Sandisk C2 16G(1)
Code:
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: All In Test
Result Type: Average
Type: Read Write
Sequential 11.477 4.897
Random 11.104 4.289
Random 4KB (QD=1) 0.965 1.732
Random 4KB (QD=32 0.968 1.78
-----------------------------------------------------------------------
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 11.946 11.898 11.899 12.166 12.128 12.0074
Random 11.499 11.494 11.487 11.392 11.695 11.5134
Random 4KB (QD=1) 0.938 0.965 0.982 0.963 0.973 0.9642
Random 4KB (QD=32 1.074 0.846 1.011 0.883 0.907 0.9442
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.471 4.482 4.974 5.331 4.994 4.8504
Random 4.127 4.147 7.171 4.175 4.143 4.7526
Random 4KB (QD=1) 1.734 1.736 1.72 1.742 1.746 1.7356
Random 4KB (QD=32 1.584 1.792 1.791 1.802 1.804 1.7546
-----------------------------------------------------------------------
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 11.939 12.013 11.887 12.112 12.241 12.0384
Random 11.198 11.421 11.382 11.653 11.614 11.4536
Random 4KB (QD=1) 0.966 0.974 0.97 0.951 0.975 0.9672
Random 4KB (QD=32 0.991 1.043 0.839 0.954 0.963 0.958
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 5.332 5.257 4.504 5.32 5.093 5.1012
Random 4.115 4.107 4.135 4.199 4.149 4.141
Random 4KB (QD=1) 1.726 1.725 1.727 1.744 1.745 1.7334
Random 4KB (QD=32 1.784 1.798 1.79 1.796 1.792 1.792
-----------------------------------------------------------------------
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 10.294 10.535 10.282 10.37 10.458 10.3878
Random 10.087 10.638 10.504 10.222 10.284 10.347
Random 4KB (QD=1) 0.969 0.997 0.957 0.931 0.973 0.9654
Random 4KB (QD=32 1.05 0.917 1.064 1.042 0.937 1.002
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.675 4.585 4.618 4.671 5.162 4.7422
Random 3.883 3.936 3.881 4.168 4.003 3.9742
Random 4KB (QD=1) 1.719 1.72 1.716 1.743 1.748 1.7292
Random 4KB (QD=32 1.786 1.79 1.789 1.8 1.806 1.7942
Sandisk C4 8G(1)
Code:
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: All In Test
Result Type: Average
Type: Read Write
Sequential 6.677 4.563
Random 6.564 3.496
Random 4KB (QD=1) 0.874 0.522
Random 4KB (QD=32 0.808 0.529
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 6.458 6.606 6.482 6.737 6.744 6.6054
Random 6.294 6.45 6.318 6.575 6.551 6.4376
Random 4KB (QD=1) 0.869 0.882 0.867 0.879 0.848 0.869
Random 4KB (QD=32 0.723 0.831 0.811 0.834 0.835 0.8068
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.414 4.624 4.697 4.785 4.983 4.7006
Random 3.055 3.811 3.751 3.733 3.733 3.6166
Random 4KB (QD=1) 0.257 0.592 0.589 0.586 0.593 0.5234
Random 4KB (QD=32 0.293 0.594 0.587 0.592 0.589 0.531
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 6.431 6.593 6.498 6.718 6.756 6.5992
Random 6.283 6.432 6.279 6.571 6.581 6.4292
Random 4KB (QD=1) 0.854 0.862 0.837 0.863 0.853 0.8538
Random 4KB (QD=32 0.722 0.81 0.832 0.818 0.826 0.8016
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.544 4.633 4.832 4.761 4.907 4.7354
Random 3.055 3.707 3.776 3.742 3.729 3.6018
Random 4KB (QD=1) 0.264 0.584 0.585 0.59 0.588 0.5222
Random 4KB (QD=32 0.294 0.582 0.583 0.597 0.591 0.5294
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 6.762 6.843 6.843 6.844 6.843 6.827
Random 6.786 6.793 6.833 6.836 6.891 6.8278
Random 4KB (QD=1) 0.919 0.893 0.911 0.882 0.898 0.9006
Random 4KB (QD=32 0.737 0.854 0.83 0.835 0.839 0.819
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 2.474 4.682 4.681 4.686 4.757 4.256
Random 1.901 3.585 3.609 3.663 3.604 3.2724
Random 4KB (QD=1) 0.262 0.588 0.587 0.587 0.588 0.5224
Random 4KB (QD=32 0.301 0.589 0.58 0.583 0.586 0.5278
Sandisk C4 8G(2)
Code:
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: All In Test
Result Type: Average
Type: Read Write
Sequential 8.03 5.134
Random 8.016 1.536
Random 4KB (QD=1) 2.151 1.173
Random 4KB (QD=32 3.39 1.088
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 7.191 7.357 7.203 7.519 7.557 7.3654
Random 7.164 7.391 7.159 7.465 7.478 7.3314
Random 4KB (QD=1) 2.086 2.066 2.096 2.106 2.107 2.0922
Random 4KB (QD=32 2.059 2.09 2.07 2.09 2.11 2.0838
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 6.308 5.457 5.817 5.624 5.911 5.8234
Random 1.475 1.605 1.629 1.732 1.725 1.6332
Random 4KB (QD=1) 1.121 1.3 1.143 1.151 1.171 1.1772
Random 4KB (QD=32 1.197 1.077 1.088 1.084 0.998 1.0888
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 7.171 7.195 7.38 7.512 7.522 7.356
Random 7.129 7.143 7.437 7.468 7.495 7.3344
Random 4KB (QD=1) 2.094 2.095 2.107 2.106 2.111 2.1026
Random 4KB (QD=32 2.065 2.074 20.88 2.097 2.088 5.8408
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 6.308 5.653 5.847 5.942 5.883 5.9266
Random 1.484 1.633 1.686 1.555 1.696 1.6108
Random 4KB (QD=1) 1.297 1.108 1.134 1.173 1.131 1.1686
Random 4KB (QD=32 1.124 1.099 0.89 0.925 0.884 0.9844
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 9.368 9.371 9.378 9.37 9.371 9.3716
Random 9.383 9.421 9.376 9.376 9.373 9.3858
Random 4KB (QD=1) 2.265 2.26 2.246 2.262 2.265 2.2596
Random 4KB (QD=32 2.241 2.245 2.251 2.268 2.234 2.2478
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.848 3.36 3.346 3.374 3.345 3.6546
Random 1.533 1.343 1.318 1.321 1.316 1.3662
Random 4KB (QD=1) 1.311 1.131 1.036 1.13 1.272 1.176
Random 4KB (QD=32 1.331 1.134 1.083 1.179 1.246 1.1946
PNY C10 8G(1)
Code:
Memory Card: PNY C10 8G(1)
Adapter/Reader: All In Test
Result Type: Average
Type: Read Write
Sequential 16.519 10.555
Random 16.52 1.434
Random 4KB (QD=1) 2.987 0.014
Random 4KB (QD=32 3.096 0.027
-----------------------------------------------------------------------
Memory Card: PNY C10 8G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 16.51 16.422 16.412 16.783 16.753 16.576
Random 16.448 16.394 16.394 16.71 16.78 16.5452
Random 4KB (QD=1) 2.95 2.949 2.955 2.971 2.944 2.9538
Random 4KB (QD=32 3.094 3.094 3.088 3.091 3.1 3.0934
Memory Card: PNY C10 8G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 10.924 10.827 10.934 11.175 11.172 11.0064
Random 1.434 1.439 1.437 1.441 1.441 1.4384
Random 4KB (QD=1) 0.015 0.015 0.015 0.015 0.015 0.015
Random 4KB (QD=32 0.026 0.03 0.027 0.027 0.028 0.0276
-----------------------------------------------------------------------
Memory Card: PNY C10 8G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 16.433 16.446 16.374 16.697 16.753 16.5406
Random 16.407 16.282 16.472 16.676 16.777 16.5228
Random 4KB (QD=1) 3.009 2.931 2.953 3.049 3.084 3.0052
Random 4KB (QD=32 3.089 3.083 3.081 3.096 3.1 3.0898
Memory Card: PNY C10 8G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 10.937 10.84 10.955 11.251 11.197 11.036
Random 1.437 1.45 1.441 1.444 1.442 1.4428
Random 4KB (QD=1) 0.015 0.013 0.015 0.015 0.014 0.0144
Random 4KB (QD=32 0.032 0.029 0.028 0.026 0.025 0.028
-----------------------------------------------------------------------
Memory Card: PNY C10 8G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 16.402 16.448 16.31 16.612 n/a 16.443
Random 16.433 16.497 16.376 16.673 n/a 16.49475
Random 4KB (QD=1) 3.001 3.097 2.938 2.982 n/a 3.0045
Random 4KB (QD=32 3.098 3.112 3.1 3.116 n/a 3.1065
Memory Card: PNY C10 8G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 9.56 9.571 9.58 9.79 n/a 9.62525
Random 1.423 1.423 1.42 1.428 n/a 1.4235
Random 4KB (QD=1) 0.014 0.015 0.015 0.014 n/a 0.0145
Random 4KB (QD=32 0.029 0.029 0.025 0.029 n/a 0.028
DaneElec C4 4G(1)
Code:
Memory Card: DaneElec C4 4G(1)
Adapter/Reader: All In Test
Result Type: Average
Type: Read Write
Sequential 16.477 10.167
Random 16.435 1.885
Random 4KB (QD=1) 2.653 0.017
Random 4KB (QD=32 2.645 0.037
-----------------------------------------------------------------------
Memory Card: DaneElec C4 4G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 16.713 16.678 16.618 17.103 17.134 16.8492
Random 16.671 16.607 16.51 16.967 17 16.751
Random 4KB (QD=1) 2.632 2.639 2.634 2.658 2.741 2.6608
Random 4KB (QD=32 2.65 2.647 2.642 2.649 2.655 2.6486
Memory Card: DaneElec C4 4G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 10.529 10.597 10.583 11.136 11.071 10.7832
Random 1.926 1.781 1.862 1.943 1.947 1.8918
Random 4KB (QD=1) 0.017 0.017 0.017 0.017 0.017 0.017
Random 4KB (QD=32 0.036 0.041 0.034 0.039 0.038 0.0376
-----------------------------------------------------------------------
Memory Card: DaneElec C4 4G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 16.764 16.655 16.599 17.072 17.173 16.8526
Random 13.618 16.51 16.536 16.929 17.017 16.122
Random 4KB (QD=1) 2.636 2.643 2.643 2.635 2.654 2.6422
Random 4KB (QD=32 2.637 2.648 2.644 2.653 2.67 2.6504
Memory Card: DaneElec C4 4G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 10.723 10.71 10.538 11.128 11.032 10.8262
Random 1.924 1.93 1.86 1.952 1.945 1.9222
Random 4KB (QD=1) 0.017 0.017 0.017 0.017 0.017 0.017
Random 4KB (QD=32 0.039 0.038 0.034 0.037 0.038 0.0372
-----------------------------------------------------------------------
Memory Card: DaneElec C4 4G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 15.683 15.664 15.639 15.936 n/a 15.7305
Random 16.323 16.343 16.358 16.71 n/a 16.4335
Random 4KB (QD=1) 2.655 2.661 2.652 2.668 n/a 2.659
Random 4KB (QD=32 2.633 2.636 2.633 2.65 n/a 2.638
Memory Card: DaneElec C4 4G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 8.784 8.824 8.827 9.136 n/a 8.89275
Random 1.837 1.836 1.843 1.858 n/a 1.8435
Random 4KB (QD=1) 0.017 0.017 0.017 0.017 n/a 0.017
Random 4KB (QD=32 0.037 0.04 0.037 0.037 n/a 0.03775
PNY 2G(1)
Code:
Memory Card: PNY 2G(1)
Adapter/Reader: All In Test
Result Type: Average
Type: Read Write
Sequential 12.607 7.829
Random 12.35 1.199
Random 4KB (QD=1) 2.091 0.01
Random 4KB (QD=32 2.464 0.027
-----------------------------------------------------------------------
Memory Card: PNY 2G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 13.261 13.263 13.266 13.27 13.275 13.267
Random 12.915 12.906 12.919 12.917 12.939 12.9192
Random 4KB (QD=1) 2.093 2.086 2.08 2.117 2.101 2.0954
Random 4KB (QD=32 2.493 2.478 2.467 2.486 2.488 2.4824
Memory Card: PNY 2G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 8.369 8.398 8.399 8.513 8.503 8.4364
Random 1.224 1.227 1.232 1.231 1.231 1.229
Random 4KB (QD=1) 0.011 0.011 0.011 0.011 0.011 0.011
Random 4KB (QD=32 0.03 0.027 0.03 0.026 0.026 0.0278
-----------------------------------------------------------------------
Memory Card: PNY 2G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 13.285 13.288 13.265 13.27 13.273 13.2762
Random 12.917 12.913 12.904 12.915 12.915 12.9128
Random 4KB (QD=1) 2.119 2.116 2.08 2.103 2.126 2.1088
Random 4KB (QD=32 2.489 2.471 2.452 2.484 2.481 2.4754
Memory Card: PNY 2G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 8.402 8.416 8.409 8.521 8.532 8.456
Random 1.227 1.23 1.23 1.231 1.232 1.23
Random 4KB (QD=1) 0.011 0.011 0.011 0.011 0.011 0.011
Random 4KB (QD=32 0.025 0.026 0.028 0.027 0.029 0.027
-----------------------------------------------------------------------
Memory Card: PNY 2G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 11.265 11.307 11.28 11.26 n/a 11.278
Random 11.211 11.232 11.218 11.222 n/a 11.22075
Random 4KB (QD=1) 2.083 2.07 2.06 2.068 n/a 2.07025
Random 4KB (QD=32 2.44 2.439 2.429 2.441 n/a 2.43725
Memory Card: PNY 2G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 6.572 6.582 6.582 6.652 n/a 6.597
Random 1.126 1.197 1.126 1.111 n/a 1.14
Random 4KB (QD=1) 0.01 0.01 0.01 0.01 n/a 0.01
Random 4KB (QD=32 0.027 0.027 0.026 0.032 n/a 0.028
*Note: After this test I switched my "tag" for ach of the SanDisk C4 8G cards in this test.
For these results in this post only:
- SanDisk C4 8G (1) is actually listed in my hardware post as SanDisk C4 8G (2).
- SanDisk C4 8G (2) is actually listed in my hardware post as SanDisk C4 8G (1).
Sorry for any confusion this may cause.

Thread Navigation:
Post 01 - Introduction, what this thread is about.
Post 02 - Benchmark Software, Memory Specifications.
Post 03 - Hardware: Computer, MicroSD cards, and Adapters/Readers.
Post 04 - Step by Step Procedures.
Post 05 - Results: Initial Test
Post 06 - Results: Test 2
Post 07 - Results: Averages
Post 08 - Results: Averages: SanDisk
Post 09 - Review/Questions/Notes.
Post 10 - Reserved
(Link to single post, reference purposes. Post 01 to reload whole thread.)
Test results (baseline part 2)
Direct Comparison of SD Adapter speed vs. USB Reader speed.
250 of 250 tests run.
-5 SanDisk class 4, 8 Gig MicroSD cards.
-5 SanDisk MicroSD to SD card Adapters.
-5 SanDisk MicroSD USB Readers.
Tested memory cards one at a time in each adapter/reader, per procedure listed above.
Reformat and re-install of windows after all cards tested in each adapter. Repeated 5 times total. Each time between formatting was one segment.
Again, averages truncated (not rounded) to 3 places past the decimal before averaging again.
Averaged the results as such:
-listed raw results in spreadsheet, averaged all SD Adapters per segment, and all USB Readers per segment. This gave me 5 SD Adapter averages per card, and 5 USB Reader averages per card.
This is the first spreadsheet called "Test 2". Each card is it's own page.
-Took those averages and laid them out in a new spreadsheet called "Averages".
-I then averaged together the SD Adapter and USB Reader averages per card, found on the page "All Results" in the "Averages" spreadsheet.
-Those numbers were copied forward to the page "Segment Averages" in the "Averages" spreadsheet. I once again averaged them together to give me a combined average, per segment.
-These segment averages were copied over to the last page of the spreadsheet, called "Combined Averages". These are the numbers I was working for.
-The Segment Averages were splayed out and compared to each other, showing the difference in SD Adapter speed vs. USB Reader speed. The results were pretty consistent.
-The Segment Averages were also averaged together to give me a 'grand total' for SD Adapter speed and USB Reader speed.
Some averages are laid out in code blocks below for casual viewing, but there is much more in the spreadsheets for anyone interested.
(also, the spreadsheets are formatted with color for easy viewing)
Grand Total Combined Averages:
Code:
Total Combined Average, SD
Memory Card: SanDisk C4 8G
Adapter: SD
Type: Read Write
Sequential 7.009 4.945
Random 6.905 3.055
Random 4KB (QD=1) 1.395 0.691
Random 4KB (QD=32 1.373 0.655
Total Combined Average, USB
Memory Card: SanDisk C4 8G
Adapter: USB
Type: Read Write
Sequential 8.884 5.117
Random 8.679 2.736
Random 4KB (QD=1) 1.48 0.742
Random 4KB (QD=32 1.441 0.719
Grand Total Combined Averages: (Side by Side)
Code:
Combined Average, Read, Side by Side
Memory Card: SanDisk C4 8G
Adapter / Reader: SD USB
Type: Read Read
Sequential 7.009 8.884
Random 6.905 8.679
Random 4KB (QD=1) 1.395 1.48
Random 4KB (QD=32 1.373 1.441
Combined Average, Write, Side by Side
Memory Card: SanDisk C4 8G
Adapter / Reader: SD USB
Type: Write Write
Sequential 4.945 5.117
Random 3.055 2.736
Random 4KB (QD=1) 0.691 0.742
Random 4KB (QD=32 0.655 0.719
Total Combined Averages by Segment: (Side by Side)
Code:
Combined Average, Read, By Segment (Side by Side SD / USB)
Memory Card: SanDisk C4 8G
Segment: 1 2 3 4 5
Adapter / Reader: SD USB SD USB SD USB SD USB SD USB
Type: Read Read Read Read Read Read Read Read Read Read
Sequential 6.827 8.884 7.051 8.886 7.059 8.884 7.053 8.879 7.058 8.887
Random 6.724 8.683 6.943 8.67 6.949 8.686 6.952 8.676 6.959 8.683
Random 4KB (QD=1) 1.391 1.476 1.399 1.476 1.397 1.481 1.396 1.486 1.396 1.485
Random 4KB (QD=32 1.371 1.441 1.371 1.439 1.374 1.446 1.375 1.442 1.375 1.44
Combined Average, Write, By Segment (Side by Side SD / USB)
Memory Card: SanDisk C4 8G
Segment: 1 2 3 4 5
Adapter / Reader: SD USB SD USB SD USB SD USB SD USB
Type: Write Write Write Write Write Write Write Write Write Write
Sequential 4.832 5.049 4.966 5.136 4.954 5.113 4.975 5.141 5 5.15
Random 2.838 2.693 2.886 2.742 3.77 2.737 2.879 2.758 2.904 2.752
Random 4KB (QD=1) 0.698 0.759 0.713 0.746 0.604 0.735 0.726 0.739 0.716 0.735
Random 4KB (QD=32 0.66 0.716 0.653 0.715 0.6 0.729 0.691 0.718 0.674 0.72
We can see quite clearly that the USB Reader showed the card at a consistently faster speed then the SD Adapter did.
The data in these spreadsheets can also be used to show a great many other things, which is one reason why I made sure to lay it out as clearly as I could.
As before, the original benchmark results generated by the program are saved to notepad files, by memory card, in folders according to segment. (test2.zip)
It was a total of 2000 numbers I transferred to the first spreadsheet. I checked my work but the possibility exists that I made a mistake somewhere. If someone notices please post below so I can correct - Thanks!
*Note: I switched the SanDisk C4 8G (1) and (2) cards from the first round of testing to the second. Since card (2) tested consistently faster then card (1), I made it the new card (1) and the slower one became the new card (2).
This worked out well, since the rest of the cards tested about the same as the new card (2), with one the new card (1) standing out above the rest in speed. It made it easier to read the results as well.
- 6/13: uploaded individual files while on vacation, zipped it together like the prior test and re-uploaded that zip as the attachment to this test.

Results: Averages
Results:Averages
Lots more to come.
I need time to process the data to get this part together.
Until the second half of the initial test is done with the new card readers this posting would just duplicate the first test results post.
I will update this when I finish the second test.

Results: SanDisk Averages.
Thread Navigation:
Post 01 - Introduction, what this thread is about.
Post 02 - Benchmark Software, Memory Specifications.
Post 03 - Hardware: Computer, MicroSD cards, and Adapters/Readers.
Post 04 - Step by Step Procedures.
Post 05 - Results: Initial Test
Post 06 - Results: Test 2
Post 07 - Results: Averages
Post 08 - Results: Averages: SanDisk
Post 09 - Review/Questions/Notes.
Post 10 - Reserved
(Link to single post, reference purposes. Post 01 to reload whole thread.)
*Note: This post will be updated later, I need time to average all the results from both tests for me to add to this one.
Results of SanDisk Memory cards.
Seems to be that the SanDisk cards perform the best, and so i'll isolate those results into their own posting for easy reference.
Below are the results by Card, largest capacity first.
Updates: n/a
Sandisk C2 16G(1)
Code:
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: All In Test
Result Type: Average
Type: Read Write
Sequential 11.477 4.897
Random 11.104 4.289
Random 4KB (QD=1) 0.965 1.732
Random 4KB (QD=32 0.968 1.78
-----------------------------------------------------------------------
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 11.946 11.898 11.899 12.166 12.128 12.0074
Random 11.499 11.494 11.487 11.392 11.695 11.5134
Random 4KB (QD=1) 0.938 0.965 0.982 0.963 0.973 0.9642
Random 4KB (QD=32 1.074 0.846 1.011 0.883 0.907 0.9442
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.471 4.482 4.974 5.331 4.994 4.8504
Random 4.127 4.147 7.171 4.175 4.143 4.7526
Random 4KB (QD=1) 1.734 1.736 1.72 1.742 1.746 1.7356
Random 4KB (QD=32 1.584 1.792 1.791 1.802 1.804 1.7546
-----------------------------------------------------------------------
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 11.939 12.013 11.887 12.112 12.241 12.0384
Random 11.198 11.421 11.382 11.653 11.614 11.4536
Random 4KB (QD=1) 0.966 0.974 0.97 0.951 0.975 0.9672
Random 4KB (QD=32 0.991 1.043 0.839 0.954 0.963 0.958
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 5.332 5.257 4.504 5.32 5.093 5.1012
Random 4.115 4.107 4.135 4.199 4.149 4.141
Random 4KB (QD=1) 1.726 1.725 1.727 1.744 1.745 1.7334
Random 4KB (QD=32 1.784 1.798 1.79 1.796 1.792 1.792
-----------------------------------------------------------------------
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 10.294 10.535 10.282 10.37 10.458 10.3878
Random 10.087 10.638 10.504 10.222 10.284 10.347
Random 4KB (QD=1) 0.969 0.997 0.957 0.931 0.973 0.9654
Random 4KB (QD=32 1.05 0.917 1.064 1.042 0.937 1.002
Memory Card: Sandisk C2 16G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.675 4.585 4.618 4.671 5.162 4.7422
Random 3.883 3.936 3.881 4.168 4.003 3.9742
Random 4KB (QD=1) 1.719 1.72 1.716 1.743 1.748 1.7292
Random 4KB (QD=32 1.786 1.79 1.789 1.8 1.806 1.7942
Sandisk C4 8G(1)
Code:
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: All In Test
Result Type: Average
Type: Read Write
Sequential 6.677 4.563
Random 6.564 3.496
Random 4KB (QD=1) 0.874 0.522
Random 4KB (QD=32 0.808 0.529
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 6.458 6.606 6.482 6.737 6.744 6.6054
Random 6.294 6.45 6.318 6.575 6.551 6.4376
Random 4KB (QD=1) 0.869 0.882 0.867 0.879 0.848 0.869
Random 4KB (QD=32 0.723 0.831 0.811 0.834 0.835 0.8068
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.414 4.624 4.697 4.785 4.983 4.7006
Random 3.055 3.811 3.751 3.733 3.733 3.6166
Random 4KB (QD=1) 0.257 0.592 0.589 0.586 0.593 0.5234
Random 4KB (QD=32 0.293 0.594 0.587 0.592 0.589 0.531
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 6.431 6.593 6.498 6.718 6.756 6.5992
Random 6.283 6.432 6.279 6.571 6.581 6.4292
Random 4KB (QD=1) 0.854 0.862 0.837 0.863 0.853 0.8538
Random 4KB (QD=32 0.722 0.81 0.832 0.818 0.826 0.8016
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.544 4.633 4.832 4.761 4.907 4.7354
Random 3.055 3.707 3.776 3.742 3.729 3.6018
Random 4KB (QD=1) 0.264 0.584 0.585 0.59 0.588 0.5222
Random 4KB (QD=32 0.294 0.582 0.583 0.597 0.591 0.5294
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 6.762 6.843 6.843 6.844 6.843 6.827
Random 6.786 6.793 6.833 6.836 6.891 6.8278
Random 4KB (QD=1) 0.919 0.893 0.911 0.882 0.898 0.9006
Random 4KB (QD=32 0.737 0.854 0.83 0.835 0.839 0.819
Memory Card: Sandisk C4 8G(1)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 2.474 4.682 4.681 4.686 4.757 4.256
Random 1.901 3.585 3.609 3.663 3.604 3.2724
Random 4KB (QD=1) 0.262 0.588 0.587 0.587 0.588 0.5224
Random 4KB (QD=32 0.301 0.589 0.58 0.583 0.586 0.5278
Sandisk C4 8G(2)
Code:
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: All In Test
Result Type: Average
Type: Read Write
Sequential 8.03 5.134
Random 8.016 1.536
Random 4KB (QD=1) 2.151 1.173
Random 4KB (QD=32 3.39 1.088
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 7.191 7.357 7.203 7.519 7.557 7.3654
Random 7.164 7.391 7.159 7.465 7.478 7.3314
Random 4KB (QD=1) 2.086 2.066 2.096 2.106 2.107 2.0922
Random 4KB (QD=32 2.059 2.09 2.07 2.09 2.11 2.0838
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: Sandisk SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 6.308 5.457 5.817 5.624 5.911 5.8234
Random 1.475 1.605 1.629 1.732 1.725 1.6332
Random 4KB (QD=1) 1.121 1.3 1.143 1.151 1.171 1.1772
Random 4KB (QD=32 1.197 1.077 1.088 1.084 0.998 1.0888
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 7.171 7.195 7.38 7.512 7.522 7.356
Random 7.129 7.143 7.437 7.468 7.495 7.3344
Random 4KB (QD=1) 2.094 2.095 2.107 2.106 2.111 2.1026
Random 4KB (QD=32 2.065 2.074 20.88 2.097 2.088 5.8408
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: DaneElec SD(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 6.308 5.653 5.847 5.942 5.883 5.9266
Random 1.484 1.633 1.686 1.555 1.696 1.6108
Random 4KB (QD=1) 1.297 1.108 1.134 1.173 1.131 1.1686
Random 4KB (QD=32 1.124 1.099 0.89 0.925 0.884 0.9844
-----------------------------------------------------------------------
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Read Read Read Read Read Read
Sequential 9.368 9.371 9.378 9.37 9.371 9.3716
Random 9.383 9.421 9.376 9.376 9.373 9.3858
Random 4KB (QD=1) 2.265 2.26 2.246 2.262 2.265 2.2596
Random 4KB (QD=32 2.241 2.245 2.251 2.268 2.234 2.2478
Memory Card: Sandisk C4 8G(2)
Adapter/Reader: DaneElec USB(1)
Test: Test 1 Test 2 Test 3 Test 4 Test 5 Average
Type: Write Write Write Write Write Write
Sequential 4.848 3.36 3.346 3.374 3.345 3.6546
Random 1.533 1.343 1.318 1.321 1.316 1.3662
Random 4KB (QD=1) 1.311 1.131 1.036 1.13 1.272 1.176
Random 4KB (QD=32 1.331 1.134 1.083 1.179 1.246 1.1946

Review, Questions and Notes.
Forthcoming, need more time to compute the data. For the time being, i'll just add little bits here and there until I get my questions sorted.
Review:
It seems like the USB Readers test consistently faster then the MicroSD to SD adapters. The laptop having an on-board SD card slot allowed me to eliminate as much hardware as possible from between the adapter to the computer, not having to use an external device.
Semi-surprising that there was a discrepancy. I expect there to be a discrepancy when I get to the part of testing in the Nook, as someone testing in that or a phone has much more then a simple card reader to test through. That the MicroSD to SD adapter presents more of a data bottleneck to the MicroSD card then the USB reader was an unknown question at the start.
This post in the thread psychoace post#16 - Voltage points to more explanation of why.
Questions:
- 6/13: Since we are starting to see the cards read consistently at different speeds depending upon which hardware is used to interface with the computer, which method more accurately represents the cards speed?
-6/13: Are the results proving consistent enough to determine a percentage of average difference between different methods of testing the card, so we can compare results?
For instance: Someone posts a benchmark from using a USB reader, someone else posts a benchmark using the nook itself to run the test, can we compare those results adjusting for the different methods used to run the test?
Notes:
- 5/31: Now that I have 5 duplicate MicroSD cards, I will be using these exclusively for this testing procedure. The other MicroSD cards will be benched against the adapters for part 2 to establish a baseline comparison, then assigned duties in my various digital devices...now that I know which ones will work best in what.
-6/13: My preliminary test showed that there was a big enough difference in speed to purchase the hardware to run test 2. Test 2 is starting to show a consistent difference between using a MicroSD to SD adapter vs. a USB reader to run the benchmark test.
Next up should be a series of tests in the Nook itself to start to determine the difference in speed using those same cards.

This post reserved.

First
So anyways, How does all of this factor with the different classes of sdcards? I thought it all depended on what class you had as to what write speed you got, but that they all (more or less) had equivalent read speeds?

Speeddymon said:
So anyways, How does all of this factor with the different classes of sdcards? I thought it all depended on what class you had as to what write speed you got, but that they all (more or less) had equivalent read speeds?
Click to expand...
Click to collapse
This is one of the things i'm trying to take a closer look at.
I was surprised to note that my class 10 card performed so poorly in testing. The packaging touted it as "for high performance and fast transfer speeds", essentially screaming it was class 10 sitting on the shelf.
At the time, that was exactly what I thought I needed, and i'm still glad to have it for testing. It's benched pretty decent so far for large file transfer, which is i'm sure what they had in mind behind the advertising and focus of the card.
I'm going to refrain from commenting just yet on the idea that they all have equivalent read speeds - but that is a good observational question to ask.
I need more test data to form an opinion. I put this thread up now because others can get real use out of the data i've collected so far.
Tentatively, with knowledge from the parent thread and this one i'll say:
- SanDisk class 2 or 4 in 4 or 8 gig capacity is the ideal MicroSD card for running an operating system on the Nook from the sdcard.
- Right now, knowing what specific cards are manufactured to the specs necessary for OS-level file operations between the device and the memory card are the only way to know what you need.
Using a class or size as a general "go get this" isn't good enough, you have to know what manufacturer makes the card that will do what you want, since different companies have different levels of quality expectation. SanDisk is our winner at the moment.
- Most memory card manufacturers don't focus on small block read/write. Probably due to the fact that unless you run operating systems or programs from the sdcard, it doesn't really matter.
A majority of the small digital electronics in the consumer market are digital/video cameras and mp3/media players. (that take MicroSD) E-book readers are still kind of niche devices, though that's changing fast.
The tablet market is basically a new thing just coming into it's own, and the mp3/media players benefit from the same specs as the cameras.
I think it'll be a little while before we start seeing memory cards optimized for small block read/write, but it's coming. This time next year a thread like this won't have the same level of importance as it does now, you'll probably be able to go by class rating to know what you need.
Right now the best we can do is try to figure out what cards/manufacturers have actually put effort into that aspect of data transfer in their memory cards.
The more we share our test results from the same program, the more we'll be able to go spend our money on what works, and not waste time and frustration fighting with the device we are trying to enjoy.
I'll be picking up a couple of things to test on wednesday, and I go on vacation on friday. Not sure if i'll have net access when I get there, but if not i'll have plenty of time to run a whole new set of tests and then play with the data.
I still have to pull my original benchmarks from the parent thread, and compare them to the new results. I have already seen some huge discrepancies without even looking.
Asking the kind of questions like you just did are precisely how we figure this out. Once the data is there, you can make whatever comparisons you want to it.

Random thoughts in celebration of hardware aquisition victory.
I am a curious one by nature. The desire to know first-hand drives me. Sometimes you just have to see it happen, and i'm having a blast with this. A whole string of goals working towards a larger objective is really rewarding to me.
I kept trying different cards until I found the CM7 SD Speed thread and realized what I needed to look for.
By the time I got what I needed, I had enough parts and pieces to put this test together. I think I did pretty good for a first try, but while I was sitting here doing it I was thinking of what would be best.
Same card in each adapter is a better comparison, and if you have more of the same you increase the range of reliability. A certain level of sampling is necessary to make the test worth running.
Found a great sale on SanDisk C4 8G. 12.99 each at Office Max. I had intended to get them one at a time over time, but it seemed like too good of a deal to walk away from.
I now have 5 of them. This is the magic number for testing, starting with Crystal averaging 5 results in the 5x50MB test.
5 duplicate cards is about variable control and quality of results. The SanDisk class 4, 8 gig MicroSD card seems like the best blend of performance/cost/usability out of the SanDisk cards recommended.
I chose this as my ideal card for the benchmark results for a couple of reasons. If this is the ideal card to have at the moment, having backup cards at the very least. Also in an effort to relate the results to as many people as possible. If this is where someone is most likely to end up, then this is what I should test. The "luck of the draw" factor helped this happen too.
Bonus: After getting all the card reader data in, i'll already be set up to stress-test those cards on the OS. This will relate the card speed test results to a real-world performance level.(another thread for another day)
Ideal for testing would be to have 5 of the same memory card, and test in 5 of each reader. Getting the 5 test memory cards is a sounder investment from the start because that allows me to hit the accuracy i'm willing to settle on for each test run. The rest can follow.
So now I can say I have a solid test platform, the biggest variables now should be the readers themselves, which is the point in the first place. Is there anything I could be doing better? Let me know!

Hello Blue6IX,
Thank you for your efforts! This seems to be the elusive key to a smooth MicroSD resident OS.
I plan to buy the Nook Color very soon, perhaps Friday. I want to boot CM7 and later releases from the MicroSD so I do not loose a couple key B&N feature, namely the free hour of in store reading of the majority of their digital books and daily deals in the cafe. I suppose that would not be possible within Gingerbread or Honeycomb.
Also I am a bit concerned that a auto update from B&N would scramble a SD boot system and data card in use?
All right now that I have my noobie questions out of the way I thought I would post my fools errand along the Sandisk trail.
I instituted a support chat with Sandisk this morning and I will paste below the results.
CC:
Busyworked: Hello, I will be booting Android from a microsd in a Nook Color. It has been found small random write speed is the key to success. Would you please tell me the fastest such or best model # Sandisk for 8GB, 16GB & 32GB?
TECH: Hello, thank you for contacting SanDisk. My name is Matt S.. Please give me a moment while I look into your question.
Busyworked: I see you are listening still did you respond?
TECH: We used to manufacture microSD/SDHC cards in Class 2. Recently we started manufacturing them in Class 4. Class ratings measure the minimum sustained speed required for recording an even rate of video onto the card.
Busyworked: Folks have had quite differing results even with Sandisk cards. Do you have any idea where I could get a small kb random write comparison of the models you have manufactured so far?
TECH: The comparison chart for the Class 2 microSD/SDHC and Class 4 microSD/SDHC cards is not available.
Blobber: I see. Well I suppose that is all for now. Good day to you.
End.

That would imply the higher the class, the faster the writes but our testing doesn't appear to support that.
As a side question, I have seen many people comment that running from eMMC is much faster than SD card. There are also people that have claimed/inferred that the memory in the Nook is a Sandisk SD chip. I suspect it's not quite that identical but what makes it run faster from eMMC vs a fast uSD card?
1. They aren't the same?
2. The bus speed?
3. Some other system overhead?
4. They really don't run faster?
Just curious.

Blue6IX said:
I am a curious one by nature. The desire to know first-hand drives me. Sometimes you just have to see it happen, and i'm having a blast with this. A whole string of goals working towards a larger objective is really rewarding to me.
I kept trying different cards until I found the CM7 SD Speed thread and realized what I needed to look for.
By the time I got what I needed, I had enough parts and pieces to put this test together. I think I did pretty good for a first try, but while I was sitting here doing it I was thinking of what would be best.
Same card in each adapter is a better comparison, and if you have more of the same you increase the range of reliability. A certain level of sampling is necessary to make the test worth running.
Found a great sale on SanDisk C4 8G. 12.99 each at Office Max. I had intended to get them one at a time over time, but it seemed like too good of a deal to walk away from.
I now have 5 of them. This is the magic number for testing, starting with Crystal averaging 5 results in the 5x50MB test.
5 duplicate cards is about variable control and quality of results. The SanDisk class 4, 8 gig MicroSD card seems like the best blend of performance/cost/usability out of the SanDisk cards recommended.
I chose this as my ideal card for the benchmark results for a couple of reasons. If this is the ideal card to have at the moment, having backup cards at the very least. Also in an effort to relate the results to as many people as possible. If this is where someone is most likely to end up, then this is what I should test. The "luck of the draw" factor helped this happen too.
Bonus: After getting all the card reader data in, i'll already be set up to stress-test those cards on the OS. This will relate the card speed test results to a real-world performance level.(another thread for another day)
Ideal for testing would be to have 5 of the same memory card, and test in 5 of each reader. Getting the 5 test memory cards is a sounder investment from the start because that allows me to hit the accuracy i'm willing to settle on for each test run. The rest can follow.
So now I can say I have a solid test platform, the biggest variables now should be the readers themselves, which is the point in the first place. Is there anything I could be doing better? Let me know!
Click to expand...
Click to collapse
I've discussed this at length in this post here last year but from what my understanding is that card ratings is only valid if proper voltage is given. There is no standard for voltage on microsd cards as you can see here . It can vary per card depending on size and speed. Typically the larger the micro sd card the higher voltage you will need. Now because phones are tested and optimized for heat and battery life I am assuming most phone manufactures will only allow a conservative amount of voltage for that slot. This is most likely the average voltage that most microsd cards are set to. By not allowing a higher voltage it's only a small percentage of cards that will have performance issues so it's easy to assume that phone manufactures would rather have a safe phone with a long battery life then to allow peak performance for a hand full of microsd cards. This isn't exclusive to phones/androids either though. I have a Canon Rebel Xt dslr with a 8 gig 133x compact flash card. When I plug the card into my media card reader it transfers RAW pictures quick. If I use the camera to transfer pictures it's a slow slow mess. Now a days newer camera's are allowing higher voltage and so typically speeds are more acceptable (they most likely upped the voltage because they needed the speed for 1080p video, so battery life wasn't a bigger concern over transfer rate). So what seems like the best option for people who want to buy a 16gig microsd card for the nook is to just get a class 2 because you will be wasting money with anything higher.

This fella tested two 2GB Kingston MSD with identical packaging accept one stating assembled in Taiwan and the other in Japan. The Japan version he shows performing FAR better In Crystal Disk (seen at the 2 minute mark of the video) and playing Final Fantasy on portable gaming devices.
Youtube - Search title as I am too new in these forums to post links:
Kingston microSD Card Performance Test Comparison - Japan or Taiwan?
Blue6IX's new test with 5 identical cards of the same model numbers should perform with little % difference in performance. But then again there might be a surprise as QA might be sloppy especially with small writes.
I would be curious if; same brand, same class, same size, but different model # performed much different, I imagine they would and that the latest would not necessarily be the greatest.
Blue if you could confirm your sample cards each say where assemble in, and are of the same model # and post what that is asap that would be helpful.
Also if you already had a card of the same make, size and class but different M# you might like to add it to your trials. Just a thought

Good input guys, very helpful.
I picked up 3 more packages of the SanDisk MicroSD to SD card adapters, so now I have 5 of the same USB MicroSD card readers, and 5 (6) of the same MicroSD to SD Card adapters.
Using 5 of the same MicroSD cards, i'll run a full test and that should give me the most reliable results to compare transfer speed from computer to MicroSD card between an integrated card slot or USB slot with a reader.
Testing in the same USB slot each time to use the same physical circuitry will probably show the USB method to be faster, but we'll see.
busyworked said:
I would be curious if; same brand, same class, same size, but different model # performed much different, I imagine they would and that the latest would not necessarily be the greatest.
Blue if you could confirm your sample cards each say where assemble in, and are of the same model # and post what that is asap that would be helpful.
Click to expand...
Click to collapse
I'll be updating my hardware listing with all the data I can physically find on the cards. I still have a lot of time to put in to get the first 10 posts up to speed, but thats coming over the next week on my vacation. The next two days will be hectic, but after that i'll be swimming in free time.
For the minute:
-all the 8 gig class 4 SanDisk cards were copyright 2010 on the packaging.
-all the SanDisk adapter combo packs were copyright 2010 on the packaging.
-the USB MicroSD adapters are stamped with serial:'s on the device itself, i'll be including that.
ETA: ok, checked the packaging I have filed here, and came up with this:
SanDisk 8 gig class 4 MicroSD: (identical on 2 packages of card alone)
-Front lower left packaging number: 80-56-09527-008G
-Below rear UPC code: 80-56-09526-008G
(on one package of card alone)
-Front lower left packaging number: 80-59-09998-008G
-Below rear UPC code: 80-59-09997-008G
(on one package where I bought the card with an adapter)
-Front lower left packaging number: 80-56-09523-008G
-Below rear UPC code: 80-56-09528-008G
(on all 4 packages)
-Above rear UPC code: SDSDQ-008G-A11M
-Printed on package: Card made in China.
(missing one package that a card came in, sorry...)
And this:
SanDisk adapter combo: (identical on all 5 packages)
-Front lower left packaging number: 80-56-09670
-Above rear UPC code: SDDRK-121-A11M
-Printed on package: Reader and adapter made in China.
I'll edit in what goes with what when I update the hardware post.
-the memory cards have two rows of very faint print on the face, i'll have to use a magnifier to make sure I get it right. One is already in the camera case I keep my memory cards in.
Even though i'm dropping my other memory cards from testing for the moment and running with the 5 SanDisk cards i'm using, the others are available if I need data. I'll update with anything else I can figure out about them too.
The 16 gig Sandisk class 2 is my best performing card, and so that one went right into service running android on my Nook color. I'll probably keep that one off the testing circuit so I can use my Nook. (at least for now)
@ psychoace: Thanks for the links and info, that hit next on my required reading list. It'll help explain why i'm getting whatever results I get in the comparison between integrated adapter and USB port.
Look like just the stuff I was going to go looking for while I was waiting for cards during testing. (on my nook, not the testing pc) I wish I had the time to read it now, i'm dying to go through it.
This also helps to explain to me why the 16 gig class 2 card is the one i'm using in my Nook.
@ awats: I never ran android from the eMMC, so I can't really answer for sure.
I would venture that it is probably faster, on identical installs just one on sdcard. The eMMC doesn't swap in and out, so the contacts don't get worn in the circuitry.
Swapping cards in and out of the Nook all the time will eventually wear the contacts inside, as well as any contamination of grease (fingers touching card contacts), dirt or whatever that acts as a resistor impeding current.
The circuitry pathway is probably shorter and runs on a faster bus in the eMMC then the SD card gets, but that is conjecture because I haven't looked too closely at the teardowns yet.
My un-enlightened opinion says that eMMC running faster is logical, but i've never played with a Nook running android on eMMC so I can't say for sure.
Maybe someone will come through here who can give you a better answer, i'm curious too.
ETA: btw - that tech log was helpful towards confirming what we are starting to realize: MicroSD cards are not optimized (at this time) for what we are doing with them. The target market is audio/video record/playback. Running an operating system requires more of different aspects of the card, and manufacturers haven't really realized it yet.

"(on all 4 packages)
-Above rear UPC code: SDSDQ-008G-A11M
-Printed on package: Card made in China."
Super, thanks BlueIX for taking the time to throw down the ID info. I actually have that model MicroSD in my Amazon saved for later cart, but will be patient about pulling the trigger.
Trying to match as close the fastest in your test I had planned on the
Model: SDSDQ-8192-E11M for my Nook but also the other as at least a couple cards is likely wise.
I realize you have a life other than your current obsession, so when ever you get time is all gravy for us. Most important enjoy your vacation time! The Sun is shinning here in Tacoma.

Along those lines if one wants to see the internal memory Google the following, it will lead to the tear down on TechRepublic or ZDnet:
SanDisk SDIN4C1 8GB Flash memory module
The full labeling on chip is:
SanDisk
SDIN4C1-8G
CHINA
0381DHK04P

[Q] Help Me Understand H2testw Results (card memory checker)

I bought a knockoff iPod off eBay a few weeks ago and it came in today. I immediately jumped online to try and find a program that can check the validity of the storage space, to make sure it's truly 16GB as it says it is. I found H2testw, which seems to be the most suggested program.
Anyway, 2 hours later, the test if finally done. I'm not exactly sure how to understand the results and would love if someone could explain it a bit to me. I've never used it, and I'm sure someone on here likely has.
I would greatly appreciate it.
(at first glance it appears it's fake or faulty and is only 7GB, not 16GB as stated but again, I don't exactly know how to understand it)
The media is likely to be defective.
7.6 GByte OK (16003088 sectors)
8.3 GByte DATA LOST (17430512 sectors)
Details:8.3 GByte overwritten (17430512 sectors)
0 KByte slightly changed (< 8 bit/sector, 0 sectors)
0 KByte corrupted (0 sectors)
8 KByte aliased memory (16 sectors)
First error at offset: 0x00000001e8602000
Expected: 0x00000001e8602000
Found: 0x00000001e8600000
H2testw version 1.3
Writing speed: 5.26 MByte/s
Reading speed: 6.73 MByte/s
H2testw v1.4
Click to expand...
Click to collapse

Yeah, I think it means 7.6GB of actual storage with 8.3GB of corrupt storage meaning the actual capacity is only 7.6GB...at least from what I read from the description on the website for the program I used.
Sample Output For A Fake 64 GB Drive
The media is likely to be defective.
3.8 GByte OK (8084847 sectors)
58.6 GByte DATA LOST (122921617 sectors)
Details:710.5 KByte overwritten (1421 sectors)
7.6 MByte slightly changed (< 8 bit/sector, 15630 sectors)
58.6 byte corrupted (122904566 sectors)
710.5 KByte aliased memory (1421 sectors)
First error at offset: 0x000000003cef8470
Expected: 0xeb7ac43a237c5170
Found: 0xeb7a843a237c5170
H2testw version 1.3
Writing speed: 9.24 MByte/s
Reading speed: 10.8 MByte/s
H2testw v1.4
Click to expand...
Click to collapse
Would still like some input from anyone who might know better then myself.

[Q] writing speed memory low

i have aproblem, my phone became recently a bit slow while downloading(torrents), i couldnt watch a yt vid(because it wpuldnt buffer, its not my internet connection that is bad and torrent didnt even took half of my bandtwith) so i did a benchmark, with some disturbing results:
sequential writing speeds: 3.74 mb/s
random writing speeds: 0.16 mb/s 42.01 iops(4k),
these benchmarks were done by androbench, they gave a ttop 10 list where there is a device with the same soc with over 15k iops random write speeds.
can this problem be solved with software or is the memory chip broken? Will a custom rom help?

Slow file transfer to phone with all methods (adb/MTP/FTP-usb-modem/FTP-802.11ac)

Hi, I experience something that I consider a very strange problem.
I recently bought a Mi 9 and discovered that its USB-typeC is only USB 2.0. This is rather disappointing, but USB 2.0 should still give 480 mbit/s = 60 MB/s transfer speed.
However, the real USB file transfer speed from PC to the phone is only 27 MB/s.
I've tried everything - MTP/PTP, adb, running FTP server on the phone through "usb modem" network.
I even setup Linux hostapd on my laptop which has 802.11ac with an Atheros chip, connected the phone to that network and got 780 mbit/s theoretical speed.
Then I started an FTP server and retested: still 27 (maybe 28-29) MB/s to the phone. At the same time, it reached the speed of 65 MB/s (=520 mbit/s) when copying a file FROM the phone to the PC.
Then I even launched Terminal emulator and started a download from the PC to the phone with `curl`. And guess what, I still got 27-30 MB/s. Even when it's downloading the file to /dev/null instead of the phone's flash memory - it still gives 27-30 MB/s.
Then I launched THREE curl's at the same time. Three of them gave me 30+30+20 MB/s = 80 MB/s = 640 mbit/s which means that my 802.11ac worked correctly.
So my question is: what is that fixed limit of 30 MB/s per process?
And what file transfer speeds do you get with your Mi9's?

vitalif said:
Hi, I experience something that I consider a very strange problem.
I recently bought a Mi 9 and discovered that its USB-typeC is only USB 2.0. This is rather disappointing, but USB 2.0 should still give 480 mbit/s = 60 MB/s transfer speed.
However, the real USB file transfer speed from PC to the phone is only 27 MB/s.
I've tried everything - MTP/PTP, adb, running FTP server on the phone through "usb modem" network.
I even setup Linux hostapd on my laptop which has 802.11ac with an Atheros chip, connected the phone to that network and got 780 mbit/s theoretical speed.
Then I started an FTP server and retested: still 27 (maybe 28-29) MB/s to the phone. At the same time, it reached the speed of 65 MB/s (=520 mbit/s) when copying a file FROM the phone to the PC.
Then I even launched Terminal emulator and started a download from the PC to the phone with `curl`. And guess what, I still got 27-30 MB/s. Even when it's downloading the file to /dev/null instead of the phone's flash memory - it still gives 27-30 MB/s.
Then I launched THREE curl's at the same time. Three of them gave me 30+30+20 MB/s = 80 MB/s = 640 mbit/s which means that my 802.11ac worked correctly.
So my question is: what is that fixed limit of 30 MB/s per process?
And what file transfer speeds do you get with your Mi9's?
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im not so technical with specs of write/read speeds but, at least i can say the same, mine to transfer around 6GB takes about 30 to 40 minuts so, i guess is around 25 to 30 mb/s, USB 2.0 on a phone this good is the only downside to have a phone without microSD slot to compensate the slow USB 2.0 speed, or worse than that.

sun_is_shinning said:
6GB takes about 30 to 40 minuts
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It's worse. 6000MB/(30*60) = 3 MB/s...
With 27MB/s it should take ~4 minutes to copy a 6 GB file...
And it should be even more, most usb 2.0 sata enclosures max out at 50-60 MB/s...

vitalif said:
It's worse. 6000MB/(30*60) = 3 MB/s...
With 27MB/s it should take ~4 minutes to copy a 6 GB file...
And it should be even more, most usb 2.0 sata enclosures max out at 50-60 MB/s...
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and i am talking about 6GB of more than 1300 pictures with ~3 to 5mb each so, probably will take more cause is not a single file.
i dont know wich method you use but i connect my phone and select MTP not PTP.
evenm its so damn slow, i regret the speed i can go with my G6 wich have usb 3.1 and thats was amazing quickly compared to Mi9.
i dont know why Xiaomi dont implement usb 3.1 on their high end models, they can make it, and even if we need to pay 10 to 20 bucks more is way way better than waste a lot of time copying files into it. - since they didnt provide microSD eighter.

My redmi note 9 also slow transfer speed but it solved now, on PC I compress all the files, transfer compressed file to the phone the extract it on the phone.

vitalif said:
This is rather disappointing, but USB 2.0 should still give 480 mbit/s = 60 MB/s transfer speed.
However, the real USB file transfer speed from PC to the phone is only 27 MB/s.
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That is the THEORETICAL MAXIMUM that USB 2.0 can achieve. In practice, NO USB 2.0 drives, I repeat, NO USB 2.0 drives ever reach that speed. The fastest one reaches only 42MBps sequential write speed and is an externally powered hard drive, while the fastest flash drive only reaches 25MBps sequential write speed (data taken from usb.userbenchmark.com, so it's sourced from multiple real world users instead of a controlled lab environment). Your 27MBps then is already a good one.