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micro SD speed Class 2 and Class 4

I have the latest ROM 2.17 intalled on my Sprint Mogul. I am searching for a larger card. I am considering a 4GB card but wanted to know if the speed is factor to consider. My understanding is that class 2 is 2MB/sec while class 4 is 4MB/sec transfer speed. Can the Mogul take advantage of this? Is the speed increase enough to really be noticeable? I am assuming the 512MB card that came with the Mogul is class 2. I cannot find any markings on the card to distingish the class.
Thank you for any help provided.

I know the answer is late...
Hi, don't know if you got an answer to your question or not. I also spent about a good three days trying to track the answer down. I never found it anywhere, called HTC they sent me to Sprint...anyways...the answer that I got was that the Mogul has an average speed of 2Mb/sec; so it may not be necessary to buy a Class 4 or 6 card if it is more expensive. It looks like price for capacity is the only real factor when looking into buying a MicroSD card for the mogul.
If any one can state different (i.e. Mogul able to read/write at a higher rated speed) that would be good to know.

It might really help to have a spare, non-SDHC card in case you need to do a ROM upgrade directly from the microSD card...
Go to NewEgg.com to find the cheapest microSD cards!

Can the HD2 benefit from class 6 SD? Or is it a bottleneck >Class 2?

I ordered a class 6 16gb card to replace the slow-ass class 2 8GB card I had in my HD2.
First of all I couldnt find the format sd tool in my energy rom (1st July) so I had to format the card using vista while the HD2 was connected in disk drive mode. THAT TOOK OVER 1 HOUR.
(Is there a cab file to install the "Format SD Card" tool for the newer energyroms?)
Anyways after formatting (Fat 32, 16KB cluster), I started to copy my 1.4GB sd backup file to the card using the same method as above (disk drive mode)....
My maximum write speed was 2.7MB/sec. Average 2MB/sec.
Class 2 speeds????
After restoring the backup, which took forever, I ran spb benchmark on the card and was gutted to get slightly lower results than the old class 2 I was replacing.
Can the HD2 make use of anything faster than a class 2 card?
Has anyone here tested a class 6 or even 4 card and found good write speeds (~6MB/sec, or ~4MB/sec)?
Does it sound like I have bought a lemon (class 2 labelled as class 6)?
I have spoken to the seller and he is adamant that they ARE genuine class 6. Reckons he tested some of the batch in TrueHD cameras which will not accept <Class6. Seems genuine and some of his feedback states that the cards are Genuine class 6. Which leads me to think that the bottleneck could be the HD2... Does that sound likely?
I'm waiting for a microsd USB reader to arrive so I can test the card outside of the HD2, but Until I can do that... can anyone tell me if a class 6 is wasted in a HD2?
The strange thing is that when browsing photos/wallpapers etc, the thumbnails ARE loading maybe 3x quicker than my old class 2. So I'm pretty confused about this one.
Can anyone shed any light here? Feel free to post benchmark results/screenshots etc.
Thanks in advance.

can anyone PLEASE answer this ^^^?
Is there any point having a class 6 card in the HD2 instead of a class 2 or 4 card?

there is a thread in the accessories section have a gander in there, I no this is Q&A's but lots of talk about mem cards in the accessories section mate

Cheers mate, I'll take a look.

I will move this thread there. I also recently bought a Class 6 card and and have seen a huge improvement in media reading and over all performence.

I get 4-5MB/s both for reads writes with my 16GB class 6 card in disk drive mode.

Thanks zelendel and kilrah.
kilrah said:
I get 4-5MB/s both for reads writes with my 16GB class 6 card in disk drive mode.
Click to expand...
Click to collapse
That is exactly the kind of data I'm looking to compare.
Whith my 'class 6' Im getting just under 3MB/S WRITE and under 6MB/S READ when using the HD2 in disk drive mode.
If I use the card in a USB 2.0 reader I can get around 5.5MB/S Write and ~11-13MB/S read.
Based on this alone would you say my card is a class 6 or not. I'm beginning to think it may be a class 4 re-labelled.
Picture browsing etc is faster with my class 6 but all benchmarks indicate it is identical speed to my genuine Kingston Class 2.
What do you guys reckon, Should I send this card back for a refund???

Well if you're getting 5.5 and over 11MB per second with a card reader then we can safely assume it's class 6. The bottleneck is something to do with the phone, rom, cable or simply the phone doesn't like this particular card etc...
EDIT: Test your class 2 card with the memory card reader and see if you get similar results.

ez2remember said:
Well if you're getting 5.5 and over 11MB per second with a card reader then we can safely assume it's class 6. The bottleneck is something to do with the phone, rom, cable or simply the phone doesn't like this particular card etc...
EDIT: Test your class 2 card with the memory card reader and see if you get similar results.
Click to expand...
Click to collapse
Thank you for helping me clear things up.
Comparing the 'class 6' and the 'class 2' transfer speeds is where I really get confused here.
Transferring a ~700MB .Avi to and from SD using a reader:
Kingston Class 2 8GB:
Read 12.5MB/s
Write 5.4MB/s
Unbranded Class 6 16GB:
Read 12.5MB/s
Write 6MB/s
So, from this, would you say its safe to assume:
1. The class 2 card is a good one, performing at almost class 6 speeds.
2. The class 6 card is 'Genuine' and shouldnt be returned.
3. There is a bottleneck when using the HD2 as a card reader/disk drive. I should be getting more than 2.5mb/s write speeds in this mode.
4? Does 12.5MB/sec sound close to USB 1.1 speeds? could my reader or even USB port (Vista laptop) be another bottleneck?
Once again thank you for helping me make sense of all this.
At least I now know that the 16gb card doesnt really need to be returned.
Can you give me your oppinions on the above?

Well class 2 means you should be getting a minimum 2MB/s speeds and class 6 means you should be getting a minimum 6MB/s.
Seems like you have a very good class 2 card.
More info here
http://en.wikipedia.org/wiki/Secure_Digital
Your class 6 is performing to spec.
Personally I would never buy an unbranded card but that's me. A branded card may perform better than there class rating e.g. Your Kingston brand I've always used Sandisk personally...

I've just managed to drum up enough funds to get myself a HD2 and now looking to upgrade my HCSD card to 16GB. To get the "right" class I tried to find the spec on the SD interface but I cannot find anything and the best data I can find is that I shouldn't waste my money on unbranded devices, I would always buy a SANDISK device for something I relied on! For data and communication!
People seem to get appropriate speeds for the class of device they have, if they are branded and sometimes if unbranded. However, there doesn't seem to be anything better than class 6 results debated or given. Is it a VERY rash assumption that the fastest the HD2 interface can go is Class 6?
Chris

Does this mean its not worth getting 32gb cos its a class2
& theat would make the phone slower cos lot more stuff on it
& will take more loading time & play Videos lagy ?
anyone useing 32gb ?
Thanks

My experience was positive with higher class micro SD.
At first, I used 8GB micro SD bundled with my HD2 and didn't notice improved loading speed. Later, I changed it with higher class one, same 8GB, with same manufacturer, Sandisk. Higher class one has name "Ultra" on it. Now with changed SD, loading became WAY faster. "Wow" I realized the higher speed of CPU of HD2.
My 2 pennies.

NEVER EVER buy unbranded memory cards!
Keep an eye on Sandisk cards only and even prefer them to Transcend and Kingston.

[Q] 32GB class 10 or class 6?

if i buy a class 10 card will the HD2 actually be able to read/write at those speeds as opposed to a class 6 or is there some internal limitation. i will buy a good quality card and test the speed when i have it.
i know that on a pc it will be faster but thats not what i want to know.
i intend to run android on sd and want the quickest card the hd2 will actually make use of.

I understand any above x 6 is wasted, use the search function suprisingly it works

Depending on what you're using the card for, you might be better getting class 2 or 4... especially if you go with Sandisk, which I recommend. Higher class cards have higher sequential write speeds, which is good for digital cameras or transferring large files, but they usually sacrifice their access times and random read, write and access speed. That's why more class 2 and 4 cards are compatible with WP7 devices than class 6 and 10, and also many have had issues with freeze-ups and performance issues when running android off a class 6 or 10 card when a class 2 or 4 performed better.
Higher class cards does not mean better in all situations, which a lot of people don't seem to know. Generally for phone use, class 2 and 4 are better. Class 6 and 10 are designed more for digital cameras or file storage. If you're going to be running apps or OS's off the card, or anything that needs to access many small bits of info quickly, Go with a high quality class 2 or 4 Sandisk.
Class ratings on cards are very misleading to people and people put too much importance in them... they only rate sequential write speed. It doesn't tell you anything else about the card, even though the other things are more important accept if you're using it for digital cameras. A new rating system needs to be made, especially since smartphones are so popular now and microSD cards are used more for cell phones than digital cameras now.

@zarathustrax: ok, thanks for the insight.
i will just get a good name card.
johnerz said:
I understand any above x 6 is wasted, use the search function suprisingly it works
Click to expand...
Click to collapse
yes, point taken,thats why i mentioned the specific way i would be using it. i actually did search but didnt find the answer for my question.

class 6 cards are not better works than class 2 or 4 cards?????
is class 6 not faster than 4

Someone managed to LEO T8585 WinMo show 32GB on microSD card?
i bought one but LEO displays cotinuosly 16GB without reset, then soft reset, then i make hard reset. I just wanna say WTF?
and custom rom is: HD2O v.19, rom is stable and wery good and i think its not rom issue.
thanks in advance.

I'm using a class 10 32gb card.
Not noticing any speed advantage over my class 4 16gb card, except for freezes because the 32gb card is not supported...
Thus you're better off using a slower, compatible card, as long as you want to use wp7

Some 32GB cards will only offer 29Gb of space. So do not only pay attention on the speed, the actual capacity will differ as well.

Some os's use 1024 * 1024 * 1024 as GB others use 1000 * 1000 * 1000, hence the difference with 32GB and 29GB (29.8GB). So no worries

[Q] SDHC 32 gig class 6

Just got NC for early Father's Day! I luv ma fam!
Everything I been finding here talks about 2,4, or 8 gigs SD cards.
NC says it can use up to 32gig.
Anyone tried this? I figure SDHC 32 G class 6 would work.

MrGeek said:
Just got NC for early Father's Day! I luv ma fam!
Everything I been finding here talks about 2,4, or 8 gigs SD cards.
NC says it can use up to 32gig.
Anyone tried this? I figure SDHC 32 G class 6 would work.
Click to expand...
Click to collapse
Everything I've read states the higher capacity cards don't do well running ROMs. Like you I'm new to the nook so I"m sure someone else with more experience will chime in.

I have a 32 gig card installed right now. Works just fine as a data card.
If you want to run custom ROMS off the card, make sure its a sandisk. That flapping sound about larger sized card being bad for Roms is a buncha crap in my opinion (and I have the benchmarks on this card to prove it), but the BRAND of card makes a huge difference when running Roms. Avoid transcend and PNY like the plague.
That said, if you just want the card for data, then yes, the NC can handle them just fine.

skwalas said:
I have a 32 gig card installed right now. Works just fine as a data card.
If you want to run custom ROMS off the card, make sure its a sandisk. That flapping sound about larger sized card being bad for Roms is a buncha crap in my opinion (and I have the benchmarks on this card to prove it), but the BRAND of card makes a huge difference when running Roms. Avoid transcend and PNY like the plague.
That said, if you just want the card for data, then yes, the NC can handle them just fine.
Click to expand...
Click to collapse
What size Sandisk card do you recommend for running custom ROMs? I've read 8 but I really would like to run a 16.

With a sandisk, I can't see any reason why a 16 or even 32 gig card would give you trouble on roms.
Using the card to run your "operating system" seems to require a higher small-block read/write speed than most cards have. Two things seem to affect it: 1) brand (sandisk is currently the only way to go), and 2)it seems that higher classed cards sacrifice the small block performance a bit. This makes sense to me, since the classification related to large block sequential read/writes (iirc), so some trade-iffs are always expected.
See this thread for useful things.
And I think most people are buying the smaller card mostly because of price, and partly due to a herd mentality on threads like the above.

Sandisk 16gb is just fine for running the Rom off the sd card; that is my current setup.

LBN1 said:
Sandisk 16gb is just fine for running the Rom off the sd card; that is my current setup.
Click to expand...
Click to collapse
What class? I'm having a hard time finding class 4.

skwalas said:
I have a 32 gig card installed right now. Works just fine as a data card.
If you want to run custom ROMS off the card, make sure its a sandisk. That flapping sound about larger sized card being bad for Roms is a buncha crap in my opinion (and I have the benchmarks on this card to prove it), but the BRAND of card makes a huge difference when running Roms. Avoid transcend and PNY like the plague.
That said, if you just want the card for data, then yes, the NC can handle them just fine.
Click to expand...
Click to collapse
Funny how all the Transcend cards in all 3 Nooks in my house are brilliant. I've used Transcend for years and have never had a problem, be it in my cameras to my phones.

Nburnes said:
Funny how all the Transcend cards in all 3 Nooks in my house are brilliant. I've used Transcend for years and have never had a problem, be it in my cameras to my phones.
Click to expand...
Click to collapse
I was referring to the specific instance of using transcend for running cm7 for example. I understand transcend and patriot are decent when used for data, and I have PNY cards in our cameras, so they seem to work fine for data.

I have a wintec SDCH 16g class 4 and it works fine, but I only use it for data.

I've been looking into this, and here's what it boils down to:
Most MicroSD cards are set up for data transfer aimed at large files, such as video or high resolution pictures. The majority of the market these cards are manufactured for are digital camcorders, cameras, and smart phones with cameras.
They've gotten great at streaming media to and from the cards, and using them as storage mediums.
Running an operating system from the card requires a whole lot of small data transfers, which is not a specification that manufacterers pay much attention to. Most people would never notice improvement in this area of the manufacturing process, so the companies don't waste money on it.
Different manufacturers have different ideas of what their product should be capable of.
SanDisk is the brand that has consistently tested better for small data transfer then other card makers.
Running programs/operating systems from a MicroSD card is a new animal, something that hasn't really been done before now, and the tablet market is still in it's infancy.
I'm sure this issue will be addressed by the hardware makers of memory cards over the next year or so, but for now we are stuck with the task of trying to figure out what works for our purpose given what's available on the market right now.
All this being said, out of a handful of cards I own, my 16 gig SanDisk class 2 MicroSD card is my highest performing card - more then twice as fast as even 4 out of 5 of the 8 gig SanDisk cards I have.
Here is the link to the software we are using to test the cards: Crystal Disk Mark
Post 5 in this thread has a link that takes you to the one that has become our communal benchmark thread, and has a lot of info on this topic.
I would surmise that a 32 gig SanDisk brand card would probably be pretty good given that:
-Sandisk 8 gig cards (in class 2 and 4) are the general recommendation
-SanDisk 16 gig cards consistently test to a higher performance level then the 8 gig cards.
If this is the beginning of a pattern, and the larger capacity SanDisk cards are inherently manufactered to a higher small data standard, then theoretically the 32 gig card would be better.
But, this is only a theory. A 32 gig card is more then just a couple of bucks, and I don't think we have enough benchmarks on them yet to say one way or another.
Even with the SanDisk 8 gig cards, there is a wide range of what you could end up with on small data transfer speed. It's kind of pot luck. Even the slowest ones are many orders of magnitude faster then most other manufacturers, though.
This would be a good thread for people who do have 32 gig cards of any brand to chime in on, so we could keep the discussion about the largest supported capacity card on the Nook seperate from the other threads on this topic.

I saw a thread a week or so ago regarding testing class 4 cards and which were better. I just ordered a NC the other day. Anyone know the thread?

Blue6IX said:
I've been looking into this, and here's what it boils down to:
Most MicroSD cards are set up for data transfer aimed at large files, such as video or high resolution pictures. The majority of the market these cards are manufactured for are digital camcorders, cameras, and smart phones with cameras.
They've gotten great at streaming media to and from the cards, and using them as storage mediums.
Running an operating system from the card requires a whole lot of small data transfers, which is not a specification that manufacterers pay much attention to. Most people would never notice improvement in this area of the manufacturing process, so the companies don't waste money on it.
Different manufacturers have different ideas of what their product should be capable of.
SanDisk is the brand that has consistently tested better for small data transfer then other card makers.
Running programs/operating systems from a MicroSD card is a new animal, something that hasn't really been done before now, and the tablet market is still in it's infancy.
I'm sure this issue will be addressed by the hardware makers of memory cards over the next year or so, but for now we are stuck with the task of trying to figure out what works for our purpose given what's available on the market right now.
All this being said, out of a handful of cards I own, my 16 gig SanDisk class 2 MicroSD card is my highest performing card - more then twice as fast as even 4 out of 5 of the 8 gig SanDisk cards I have.
Here is the link to the software we are using to test the cards: Crystal Disk Mark
Post 5 in this thread has a link that takes you to the one that has become our communal benchmark thread, and has a lot of info on this topic.
I would surmise that a 32 gig SanDisk brand card would probably be pretty good given that:
-Sandisk 8 gig cards (in class 2 and 4) are the general recommendation
-SanDisk 16 gig cards consistently test to a higher performance level then the 8 gig cards.
If this is the beginning of a pattern, and the larger capacity SanDisk cards are inherently manufactered to a higher small data standard, then theoretically the 32 gig card would be better.
But, this is only a theory. A 32 gig card is more then just a couple of bucks, and I don't think we have enough benchmarks on them yet to say one way or another.
Even with the SanDisk 8 gig cards, there is a wide range of what you could end up with on small data transfer speed. It's kind of pot luck. Even the slowest ones are many orders of magnitude faster then most other manufacturers, though.
This would be a good thread for people who do have 32 gig cards of any brand to chime in on, so we could keep the discussion about the largest supported capacity card on the Nook seperate from the other threads on this topic.
Click to expand...
Click to collapse
Thank you for a very informative post. As I mentioned earlier I'm new to the NC and your post has helped me considerably.

androidmonkey said:
I saw a thread a week or so ago regarding testing class 4 cards and which were better. I just ordered a NC the other day. Anyone know the thread?
Click to expand...
Click to collapse
You might mean my thread on comparing speed results between different readers using the benchmark software.
It's more a look at the testing software and methods of doing so then the actual cards themselves.
The more people who post benchmark results in the thread skwalas linked to back in post 5, the better of an idea we'll have of what works for us.
The amount of information we've collected so far in such a short time is astonishing - this is a great community.

harpo1 said:
What class? I'm having a hard time finding class 4.
Click to expand...
Click to collapse
Sandisk 16gb, Class 4; Got it from Radio Shack a month or so ago on sale for like $25.

32 Gig
http://www.amazon.com/gp/product/B004G7D0IW
Bought this one about a month ago. Transferred my 16G class 2 from Radio Shack to the 32G then expanded the partition. I run CM7 off the SD. Works GREAT!. I run movies, apps from the card with tons of room.

Thanks for all the replies! They been very helpful!
However...
Here is the link to the software we are using to test the cards: Crystal Disk Mark
Click to expand...
Click to collapse
I tried downloading that and it got flagged as malware by Microsoft Security Essentials.

Rocking a 32 Lexar Class 10 here. Just download SD Tools from the market and its running 11 MB/s write and 25 MB/s read.

lucas993 said:
Rocking a 32 Lexar Class 10 here. Just download SD Tools from the market and its running 11 MB/s write and 25 MB/s read.
Click to expand...
Click to collapse
IIRC, Lexar splits their Class X cards into two more classifications, a regular and an Ultra class. Which one was yours?
Also, Radio Shack currently has 8gb Sandisk C4 cards for sale at 14.99. Perfect for playing with an SD install. With Crystal mark and a cheapie USB reader I got 2.5mb/s read, 1.5 mb/s write (both of the small block ones). I believe these are the important ones for an SD card based ROM?

I suspect the main reason there's not much info out there on 32GB cards is that people are less willing to drop $50-80 on something that may not work (IF they're trying to run a custom ROM from the card). If you're not trying to set up a custom ROM install on the SD, get any card you want--you may appreciate that higher sequential read/write in the higher class cards when you're moving multiple GB of movies or music to and from the card.
From everything I've read, the size of the card makes no difference whatsoever. The only reason people harp on the 8GB and 16GB Sandisk cards is because those specific models (both class 2 and 4 in those sizes) have been tested many times and return both reliably high small-block random writes and positive anecdotal reports for running ROMs. The size, manufacturer and class are irrelevant in and of themselves: they just let us identify specific models identified as most consistently working well.
Also, CrystalDiskMark is not malware: just do a custom install and choose not to install whatever is bundled with it (do this always for all software, I'd say). It's whatever program they use to suggest other software that triggers the false positives in security programs.

[Q] Note sdcard read speed.

Hi,
I am eyeing for the sandisk mobile ultra 32gb class 6. It claims to have 30mb/s read speed which is really impressive.
But does galaxy note sdcard reader will be able to handle 30mb/s read speed? Because for what I know most card reader tops at 20mb/s which is why most cards even those class10 ones has read speeds of less than 20mb/s.
Please correct me if I am wrong.
Thanks.

I don't think Note can handle 30 mb/s .. someone with more insight on the hardware of the card reader on Note might be able to help you

I have 32GB 10 class I can help but tell me pliz how to chech the speed read write?

PetrSoap said:
I have 32GB 10 class I can help but tell me pliz how to chech the speed read write?
Click to expand...
Click to collapse
http://crystalmark.info/software/CrystalDiskMark/index-e.html

but that is for PC and as I understand we should get the test on Note with the card inserted ????

PetrSoap said:
but that is for PC and as I understand we should get the test on Note with the card inserted ????
Click to expand...
Click to collapse
That's the 'realism' that I had in my mind. If I have a full 32gb card, and wanted to transfer my pictures and videos, which is what mostly the card will be used up for, how is the transfer speed will be? If I am able to use the full 30mb/s read speed on sandisk mobile ultra card, that can greatly reduce the amount of time to move 32gb of data off the sdcard.
For sdcard application usage within the phone itself, the only thing that I can think of that will use alot of bandwidth on the card is recording full hd video, which a class 6 card is more than enough to handle the write speed. If for read speed, a mere class 2 cards can do 8mb/s read speed which is fast enough to watch your regular hd video, listen to your mp3 etc.
You just can just connect the phone to pc as storage mass and the program will detect the drive. You can start the test using the software.
What is your microsd brand?

k heres my 2 cents, my family has 5 galaxy notes. Basically I tried many brands ranging class 4, 6 and 10. First off the class 4 32g are like 40% or so slower than the class 10's. The 2 class 10's I have are all different brand both 32g and I can tell you they don't really make a lot of diff in terms of speed its less than 0.5mb per sec diff (the slower class 10 is same brand as the Note and the other one starts with Lex???). Then you have the class 6 64g which runs up to around 10% or so slower than the class 10. At the end of the day what you find is class 6 and 10 are both fast but the class 4 are dam slow. On my machine I'm using the 64g card. Speed was determined and optimized by SD booster and SD tools.

Thanks for info, that's alot of GNotes you got there.. your family must like BIG SCREENS.
Anyway, my actual question was, is the GNote be able to handle 30mb/s transfer for the sandisk mobile ultra versions or atleast what is the highest read speed for GNote card reader.
There is one benchmark that I came across somewhere that proves that the card does actually deliever that transfer speed albeit using usb 3.0 port. It takes atleast a regular usb 2.0 reader on a usb 3.0port to achieve it. A usb 2.0 reader on usb 2.0 port barely makes the 20mb/s mark on the same card. So the usb 3.0 port is quite crucial even though a usb 2.0 reader is being used on it.
So yah, the ideal situation is someone actually has the sandisk ultra mobile card + GNote and is willing to give spare time to benchmark it for us and post it here.