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Nexus 4 Undervolting

I've always been a big fan of undervolting. These are the lowest voltages I can get stable at these common speeds. I found I can underclock the Matr1x kernel further than some others I have tried for some unknown reason. How low have you been able to go? Also, what programs do you use to test stability? So far, I have been running Antutu test completion as a measure of stability. Any suggestions otherwise?
288MHz - 650mv
1.02Ghz - 800mv
1.51Ghz - 1000mv
ROM: Bionic AOSP V3
Kernel: Matr1x 6.5

Noob question~ Why do people undervolt?

WarToilet said:
Noob question~ Why do people undervolt?
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To increase battery life,

The Long answer is that the CPU has a number of parameters where Clockspeed (MHz) and voltage (mV) are two. Clockspeed, well that is speed. Voltage is related to the amount of energy provided to the cpu, undervolting means that you feed the CPU less juice but demand that it runs at the same clocks. You are essentially starving the CPU,it uses less energy, but can become unstable if the voltage is insufficient to maintain operations. Manufactures always have extra voltage as a safety margin so power users can check their CPU bin (slow, normal, fast or faster) and lower voltages step by step until they crash the phone during a stress test, increase the voltage slightly and boom, your phone uses less battery power while being just as fast.

I undervolt to reduce heat. It makes a significant difference. The battery saving is minimal, but the temperature difference is VERY noticeable.

estallings15 said:
I undervolt to reduce heat. It makes a significant difference. The battery saving is minimal, but the temperature difference is VERY noticeable.
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Took words from my mouth. This this and this. It reduces heat, which in turn reduces battery use. UV by itself doesn't save a lot of battery, it's the consequences of it. I'm normally not a fan of UV, but with current N4 sw/fw it NEEDS it. It's way too high.
Interesting observation. As of recently my phone jumps up by 3-5c from 37-38 hover. Never used to do it before, not until i got it up to 50c for about half an hour last week. Previously it would stay steadily at 37-38, now it spikes up now and again during use. What's interesting about is that once it goes over 40c battery use increases drastically. So i wonder if people that have really good battery life don't have phones that go over that temp often and vice versa.

I haven't played around with the values too much yet, just a -100mV across the board. This seems to work just fine, so I might experiment some more..
Using Franco test-r69 at the moment.
Sent from my Nexus 4 using xda premium

I undervolt to prevent heating like others say. My Antutu scores drop like a rock when I'm at stock clockspeeds mostly likely due to thermal throttling. Now I can run it repeatedly without having scores drop. It saves battery and runs faster while running games even for very short periods of time, so I am a big fan of undervolting. :good:

Undervolt to reduce power usage, think of the stock voltage as normally being more than is required, think of running for a bus yet you have 2 minutes why waste energy when you can walk and still make it .
Undervolt for less power usage and less heat produced meaning battery performance is better (cooler battery is a more efficient one) and performance is up as you avoid any thermal limits in place .
Great stuff undervolting, I have managed to get -150mV across the board ( 1.5ghz @ 1000mV) and 288mhz is 162.5mV .

I came from a nexus s ... And one member of xda went to amazing lengths to show that undervolting really made very little differences in battery life ... And it def wasn't worth the instability .
He did loads of tests and I mean loads and basically showed that in helped so little that if you had a reboot you would use more power in rebooting then saving via undervolt
However . it is worth it for the heat decrease for sure
Sent from my Nexus 4 using Tapatalk 2

italia0101 said:
I came from a nexus s ... And one member of xda went to amazing lengths to show that undervolting really made very little differences in battery life ... And it def wasn't worth the instability .
He did loads of tests and I mean loads and basically showed that in helped so little that if you had a reboot you would use more power in rebooting then saving via undervolt
However . it is worth it for the heat decrease for sure
Sent from my Nexus 4 using Tapatalk 2
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The more the heat, the faster the battery drains. Since undervolting decreases heat, im sure it should increase battery life. Maybe not for browsing or calling, but playing a heavy 3D game.

is it normal that the higher the frequency the lower the voltage in setcpu?
screenshot: http://db.tt/k6r8c5oI
I'm quite new to nexus 4 undervolting, what's the average amount i can lower the voltages with? (i have a nominal CPU)
sent from my Nexus 4...

zakoo2 said:
how can you guys undervolt? is there an app for that? i bought Franco's kernel updater app, but there's no option to undervolt in there.
edit: just found an app called setcpu, is that it?
sent from my Nexus 4...
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You can do it from franco kernel updater, from frequencies and voltages - voltages - cpu voltages
But i dont recommend you to undervolt if you dont know what you do.
Sent from my Nexus 4 using Tapatalk 2

aimcr7 said:
You can do it from franco kernel updater, from frequencies and voltages - voltages - cpu voltages
But i dont recommend you to undervolt if you dont know what you do.
Sent from my Nexus 4 using Tapatalk 2
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I'm familiar with undervolting both on PC and on phone, but i had a Motorola defy before my nexus and undervolting there was a bit different.
sent from my Nexus 4...

zakoo2 said:
is it normal that the higher the frequency the lower the voltage in setcpu?
screenshot: http://db.tt/k6r8c5oI
I'm quite new to nexus 4 undervolting, what's the average amount i can lower the voltages with? (i have a nominal CPU)
sent from my Nexus 4...
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How are you able to undervolt with SetCPU? I'm not seeing that option using CM10, and Harsh's kernel.

italia0101 said:
I came from a nexus s ... And one member of xda went to amazing lengths to show that undervolting really made very little differences in battery life ... And it def wasn't worth the instability .
He did loads of tests and I mean loads and basically showed that in helped so little that if you had a reboot you would use more power in rebooting then saving via undervolt
However . it is worth it for the heat decrease for sure
Sent from my Nexus 4 using Tapatalk 2
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Click to collapse
Former nexus s user here, the reason nexus s didn't benefit in battery life much was that it only had 1 core, and used a higher nm manufacturing process, 65nm -> 28nm. Lower voltages in the 28nm means that it multiplies the heat/power savings more than a 65nm, and the 4 cores multiply the savings by up to 4.

FatalityBoyZahy said:
How are you able to undervolt with SetCPU? I'm not seeing that option using CM10, and Harsh's kernel.
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don't know, it was just there. did you try to reboot after installing the app?
I'm on Franco's kernel btw.
sent from my Nexus 4...

Pls what are the right values for under volting Samsung captivate
Sent from my SGH-I897 using xda premium

I am new to this and my battery goes +40°C when I play simple games... I am running Franco's kernel r71 should I do UV? If so how much? Thanks in advance
Sent from my Nexus 4 using xda app-developers app

xtremer92 said:
Pls what are the right values for under volting Samsung captivate
Sent from my SGH-I897 using xda premium
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this is the lg nexus 4 forum.
sent from my Nexus 4...

Overclocking the Nexus 4 - Benchmark of application load time = BIG difference

A lot of people say that overclocking the Nexus 4 is useless as it's so fast to begin with, but that turns out to be false, yes, it's useless for making e.g. games run smoother, as they all already do, but it's very useful for reducing loading times, and it turns out that the % of time saved is close to the % of increased clock speed.
My setup: Nexus 4, franco.Kernel updater v9.3.3, Franco Kernel #666, Jelly Bean 4.2.2 JDQ39, Governor Interactive. Angry pigs HD 1.1.0 app loading. Fresh reboot for each speed. I did three measurements for each clock speed and left voltages at Franco's defaults. I would suggest looking into the undervolting threads to figure out how low you can go with voltages, undervolting is good underclocking is usually not.
1026 Mhz 1025mV default Franco
15.4s
15.9s
15.7s
1512 MHz 1150 mV default Franco
11.5s
11.3s
11.3s
1620 MHz 1175mV default Franco
11.1s
10.6s
10.6s
1674 MHz 1175mV default Franco
10.3s
10.6s
10.7s
1728 MHz 1200mV default Franco
10.5s
10.3s
10.3s
Conclusion
12.5% faster clock speed = 8.85% faster load time, which means increasing clock speed is 70% effective at reducing load time going from 1512 Mhz and upwards.
40% faster clock speed = 35% faster load time, meaning that people who think running their device at 1026 Mhz is as good as 1512 Mhz are wrong. Nearly doubling clock speed nearly halfens load time.
The reduction in loading time is reduced a bit as you reach higher frequencies, but it's still 70% effective so every extra Mhz helps cut down the wait. Overclocking the Nexus 4 is meaningless in terms of increasing smoothness IN APP, but meaningful in reducing load times significantly and in increasing the responsiveness of your system.

please tell me for saving the battery and still maintaining a little smoothness
the settings to use
i use faux123 kernel.. i just need the voltage,cpu clock n governer settings

so overclocking makes things faster.. really? who would have thunk. and you just found this out?

my brother uses a galaxy s3, and after using it for a few months he tried my n4... he was amused how fast things open and how smooth everything was, and it was all stock frequencies. i think it makes no sense overclocking this beast, it is already fast enough. +/- a few seconds doesnt make that much of a difference but drains the battery significantly more. just sayin'.

zakoo2 said:
my brother uses a galaxy s3, and after using it for a few months he tried my n4... he was amused how fast things open and how smooth everything was, and it was all stock frequencies. i think it makes no sense overclocking this beast, it is already fast enough. +/- a few seconds doesnt make that much of a difference but drains the battery significantly more. just sayin'.
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Sorry but little OC can help you save more battery in day to day usage. (If you are not playing only games on your phone).
Sent from SpeedMachine i9100

alen1901 said:
Sorry but little OC can help you save more battery in day to day usage. (If you are not playing only games on your phone).
Sent from SpeedMachine i9100
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not according to my experiences, and i did play with oc/uc and voltage quite a bit. i always ended up going back to stock on the n4 (not on my old motodefy though) because of the drainage.

So, a 50% increase in clock cycles pushes the performance by a bit.
Who would've thought...?

well that's normal, overclocking = more power draining, more speed; just like with CPU or ram on pc, no rocket science here.

alen1901 said:
Sorry but little OC can help you save more battery in day to day usage. (If you are not playing only games on your phone).
Sent from SpeedMachine i9100
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OC? Don't you mean Downclocking or Undervolting?

sigma392 said:
OC? Don't you mean Downclocking or Undervolting?
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Nope , also OC can (in theory) improve battery life because the CPU finishes its task faster.
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gohan040 said:
Nope , also OC can (in theory) improve battery life because the CPU finishes its task faster.
a pigeon delivered this message.... ** your welcome **
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But er... Wouldn't it would theoretically need more power and therefore generating more heat than stock frequencies which in turn will have a negative effect on battery life?

sigma392 said:
But er... Wouldn't it would theoretically need more power and therefore generating more heat than stock frequencies which in turn will have a negative effect on battery life?
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It REALLY depends. I'd say most day-to-day usage, an overclock can actually help save battery by 'racing' to sleep (hurry up, finish, drop to deep sleep on cpu AND radio). I think being on 3g makes it even more pronounced because you're letting the radio drop back down to a lower power state as well as the CPU. So if you need to quickly open an email attachment, and cpu is the limiter, it can help it finish, get off the network, and back to idle state faster and save some battery. Now if you go on running benchmarks instead where you just keep throwing more work at it that's a seriously different story. There is also a point of diminishing returns (usually 1 or 2 steps before the absolute limit, in our case about 1670mhz) but in general, a moderate overclock can help.

sigma392 said:
But er... Wouldn't it would theoretically need more power and therefore generating more heat than stock frequencies which in turn will have a negative effect on battery life?
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I agree with u, but remember its a theory.. U finish faster so the time it uses more power is less....
^^Look at the post above me, he got a good example^^
The best of both worlds (if your phone is capable to do this) is when u UV and OC. U would use less power on a higher frequency. Win-win in theory.
But I know what u mean and its hard to believe, but I think that's what @alan1901 wanted to say.
a pigeon delivered this message.... ** your welcome **

If you are lucky, you can overclock using STOCK voltage for the maximum clock.
IE, i see many undervolting their phones by alot. I would just try 1150mV (default voltage for 1.5ghz) for your highest speed (OC as high as you can with this voltage), which means you are not using more power, but still making your phone faster.
Haven't tried on mine, but say 1.6-1.7ghz should be possible with 1150mV for a few at least.

No, 50% OC is not = 50% reduced load time
Let me summarize:
OVERCLOCKING > UNDERCLOCKING FOR THE AVERAGE (POWER) USER
You load a lot of apps, you don't play games or watch videos for hours, productivity is your focus. Depending on use you could save probably 1 - 6 hours a year (see assumptions below). Battery gains won't be significant, but spending less time with the LCD/Wifi etc on could give you some gains as the CPU is one of the lower power drain components.
UNDERCLOCKING > OVERCLOCKING FOR THE 3D GAMER
You spent a lot of time playing CPU intensive games, keeping the CPU cores at max clock speed for extended periods of time. In that case you could get some battery life gains at the cost of responsiveness and app loading times - your call.
IN MORE DETAIL
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UNDERCLOCKING + UNDERVOLTING PROs/CONs
+ Reduces CPU temperature, if that matters to you.
+ IF keeping the CPU at max clock speed for extended periods of time, a lower max voltage could give you enough extra battery life to negate the time lost waiting for apps to load - your call.
- Increased load times - even on the Nexus 4 a lot of apps take > 10 seconds to launch, and don't forget in-app load times, reboots etc.
- No significant battery saving in most cases, potential for loss (if doing a lot of app loading you could even get worse battery life as the screen, wifi etc has to stay on for longer, and the screen is the main battery drain).
- Time spent finding stable voltages.
OVERCLOCKING PROs and CONs
+ Potential small battery life gain, as your device spends less time with the screen/wifi etc ON.
++ SAVES YOU TIME. I'm estimating 1 - 5 hours a year depending on usage.
- Times spent finding stable voltages and clock speeds.
-/- Apps does not RUN smoother.
Why 50% CPU does not = 50% reduced load time and why you test things
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It'd be more like 40-30% depending on relative clock speed. I did a simple test as we did NOT know that app loading was mainly CPU limited, could have been memory. And If load times didn't go down there wouldn't be ANY reason to OC and underclocking would be a good idea.
Assumptions behind an estimated 1 - 6 hours saved a year by overclocking
---------------------------------------------------------------------------------------------------------------------
Say that you're on average waiting 4 minutes a day waiting for apps to load, rebooting your phone, waiting for web pages to load, waiting for in-app content to load etc.
Overclocking can cut down that wait time up to 10%, that's nearly 1/2 a minute saved every day, 3 1/2 minutes a week, 3 hours a year. This means you can get a good return on the time it took you to overclock your device, assuming you'll keep it for a couple of years. So if that's the case, why not do it? You'll save some time and you'll enjoy using your device a bit more.
Currently I'm OCd at max 1674 Mhz @ 1225mV, otherwise using default Franco voltages and interactive governor. Stable and very snappy Might be able to reduce voltage and retain stability but this is fine.

zakoo2 said:
not according to my experiences, and i did play with oc/uc and voltage quite a bit. i always ended up going back to stock on the n4 (not on my old motodefy though) because of the drainage.
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sigma392 said:
OC? Don't you mean Downclocking or Undervolting?
Click to expand...
Click to collapse
I said little OC. Example. Stock cpu clock is 1000mhz and 1000mv. Now, you OC your phone to 1200,1300mhz without changing voltage, or by increasing it a little bit(+25, +50mv, to make phone stable), it will use higher cpu frequency with the same voltage like on lower frequency or with a little higher voltage. So it would finish tasks faster, going to idle faster without getting any heat and give you more battery. On my nexus s and galaxy s3, galaxy s2, i tested it, and it helped (about 30min more screen on time for me). But if you play games a lot and doing some heavy tasks then underclock and undervolt are best for you. But on that beast of phone, i woldnt underclock it beyond 1.2, 1.3, not sure what frequencies are there. If you UC that phone a lot, you can easyly go with some weaker phone.
Sent from SpeedMachine i9100

is there any kernel that can overclock with 4.3?

Andre_Vitto said:
is there any kernel that can overclock with 4.3?
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yes, most of them. some even overclock up to 2052mhz :victory:

simms22 said:
yes, most of them. some even overclock up to 2052mhz :victory:
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like?

Check the Development sections.
This thread makes my head hurt.

Question about CPU governors

I am looking for a CPU governor I can use with just the root that our AT&T Note 3's currently have. What I would like to do is have a governor so when certain games that are really draining my battery are running that it will lower the CPU and give me better battery life. Is this possible with our current root only? I read that SetCPU had this feature with app based profiles but the recent reviews are stating that the app based profiles are not working correctly. Does anyone have any suggestion of what I could use?

Set cpu is working for me, I have the paid version though. I put it on performance governor and it held 1 core wide open at 2265. I then changed it to ondemand and the core dropped to 300. There's also a conservative, interactive, user space and power save governors. Search governors for explanation of each governors settings/purpose.
Sent from my SAMSUNG-SM-N900A using xda app-developers app

kitsinni said:
I am looking for a CPU governor I can use with just the root that our AT&T Note 3's currently have. What I would like to do is have a governor so when certain games that are really draining my battery are running that it will lower the CPU and give me better battery life. Is this possible with our current root only? I read that SetCPU had this feature with app based profiles but the recent reviews are stating that the app based profiles are not working correctly. Does anyone have any suggestion of what I could use?
Click to expand...
Click to collapse
You can set a profile to lower CPU when your battery gets above a certain speed. That would be your best. Another alternative is to set a max speed for x condition or y. Doing all of the above will lower the performance of your game. It would be best to try different max speeds that still allow you to play your game enjoyably and go from there. Games are just a battery hog, even if you lower your speed it will still take milliamps than you'd prefer. I think off hand to just try, is set max speed at the 15xx speed and just use on demand or interactive. Power save will lower performance too dramatically and possibly kill more battery. Performance is really for the most demanding of games or benchmarking.
Sent from my SM900T.

@rbiter said:
You can set a profile to lower CPU when your battery gets above a certain speed. That would be your best. Another alternative is to set a max speed for x condition or y. Doing all of the above will lower the performance of your game. It would be best to try different max speeds that still allow you to play your game enjoyably and go from there. Games are just a battery hog, even if you lower your speed it will still take milliamps than you'd prefer. I think off hand to just try, is set max speed at the 15xx speed and just use on demand or interactive. Power save will lower performance too dramatically and possibly kill more battery. Performance is really for the most demanding of games or benchmarking.
Sent from my SM900T.
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so this may be a dumb question, but is 300MHz the lowest clock speed it can reach? I just installed Better Battery Stats on my Nexus 7 (2012) and it can get down to 50MHz. Just looking to conserve more battery. Thanks!

Just get a Zerolemon 10000 mah battery and never worry about what is using your battery again. They are only 50 bucks and that includes the special case/protector to house the phone and the battery.

Solarenemy68 said:
Just get a Zerolemon 10000 mah battery and never worry about what is using your battery again. They are only 50 bucks and that includes the special case/protector to house the phone and the battery.
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That's not really an option for me. I often rock the phone with no case at all and like it in its 168g form. I already have 30-40 hour batterly life with 3-4 hrs of screen time. But I just noticed the lowest clock speed it 300Mhz and I think it can be lower!

Solarenemy68 said:
Just get a Zerolemon 10000 mah battery and never worry about what is using your battery again. They are only 50 bucks and that includes the special case/protector to house the phone and the battery.
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Yes! This is my solution. No worries when mpdecision gets stuck on 4.4.2 and stops sleeping cores, who cares?! Pry-Fi running continuously in War mode, booyah.

CPU Binning and undervolt

Hi,
I saw BravoMotolora's article about CPU binning, and I thought that it would be great if we compare CPU bin and voltages.
It will be great to know the relationship between voltage and PVS number.
Please follow this procedure
1. Install a custom kernel that lets you do undervolt, e.g. franco.Kernel
2. Do what BravoMotolora said
3. Undervolt your N5 by 25MV
4. Run Antutu
Then, you might see your N5 rebooting or giving you a Antutu score.
If you get the score, go and try the procedure again
I got to -50MV with PVS1 N5.
Please post your results(undervolt that you did and your N5's PVS) here!

Can you not do this?

Do not do what? I mean most of guys here will do undervolt to save battery anyway so won't it be good to share some intel?
Sent from my Nexus 5 using XDA Premium HD app

I'm the same as OP... I have PVS 1 and the max I can UV is -50mV.

you do realize that many custom kernels set their voltages different than default/stock, and differ among themselves? for example, if you go -50mV less on using franco kernel, and go -50mV less using trinity kernel, it means nothing because their voltages differ to begin with. i mean you cant really compare each others voltages that way. you would need to write your voltages in real numbers, and cpu speed steps.

I honestly never saw a huge benefit in undervolting. It can also cause errors which lead to worse battery life.
Sent from my AOSP on HammerHead using XDA Premium 4 mobile app

johndrmr said:
I honestly never saw a huge benefit in undervolting. It can also cause errors which lead to worse battery life.
Sent from my AOSP on HammerHead using XDA Premium 4 mobile app
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agreed. i personally do better with underclocking, than with undervolting.

simms22 said:
agreed. i personally do better with underclocking, than with undervolting.
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Click to collapse
it's a lot easier to underclock 20% than to undervolt 10%, which approx. gives you the same active power savings. It's a lot safer too, if you don't have a spec sheet for the CPU handy.
underclocking does nothing to idle power (or leakage power) though

This phone does pretty well arlt idle I think. Can't imagine you would see much gain from UV.
Sent from my AOSP on HammerHead using XDA Premium 4 mobile app

klin1344 said:
I'm the same as OP... I have PVS 1 and the max I can UV is -50mV.
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I have a PVS 2 and can undervotl -75mV accross the board and -87.5mV at 300Mhz.
So 2,26Ghz I can run at 0.975 Volt.
CM11 with Bricked Kernel.
Together with Sync off, Google hotword off and optimized automatic brightness I get constantly 5 - 5,5 hours screen on time with websurfing, mail and music stream.
Marcel

menting said:
it's a lot easier to underclock 20% than to undervolt 10%, which approx. gives you the same active power savings. It's a lot safer too, if you don't have a spec sheet for the CPU handy.
underclocking does nothing to idle power (or leakage power) though
Click to expand...
Click to collapse
Underclocking drops the performance of the phone, as the peak performance is not available when needed. Undervolting on the other hand gives you battery savings without affecting peak performance at all. If done too aggressively, it can make the phone unstable, but there is never any danger of hardware damage. The instability will at most cause errors, random reboot, or a freeze up. If this happens, you know you've pushed too far under, and you can bump voltage closer to stock after booting the phone back up. If running stably, undervolting is actually marginally better for your phone hardware than stock voltage because you are wasting less of the energy in heating up the chips and damaging them.

rajendra82 said:
Underclocking drops the performance of the phone, as the peak performance is not available when needed. Undervolting on the other hand gives you battery savings without affecting peak performance at all. If done too aggressively, it can make the phone unstable, but there is never any danger of hardware damage. The instability will at most cause errors, random reboot, or a freeze up. If this happens, you know you've pushed too far under, and you can bump voltage closer to stock after booting the phone back up. If running stably, undervolting is actually marginally better for your phone hardware than stock voltage because you are wasting less of the energy in heating up the chips and damaging them.
Click to expand...
Click to collapse
i underclock, sometimes to 1036mhz max, with all 4 cores always on by default(no hotplugging). sure, in a benchmark itll score less, just like i expect to score more when im overclocked. but to the normal user, they would never be able to tell that my phone is only clocked to 1036mhz. meaning the user experience isnt lowered in any way. even intense gpu oriented games dont show that im running underclocked. so when you say it drops the performance, it isnt entirely accurate.

simms22 said:
i underclock, sometimes to 1036mhz max, with all 4 cores always on by default(no hotplugging). sure, in a benchmark itll score less, just like i expect to score more when im overclocked. but to the normal user, they would never be able to tell that my phone is only clocked to 1036mhz. meaning the user experience isnt lowered in any way. even intense gpu oriented games dont show that im running underclocked. so when you say it drops the performance, it isnt entirely accurate.
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Click to collapse
Sorry, but CPU underclocking means always a drop in CPU performance.
When you compensate this drop in your case by always having all four cores active you produce more heat with the active cores.
(and I estimate it will produce more heat/battery depletion than the original phone settings. (max 2,26Ghz and variable core usage)
When you argue that in general a normal user is not realizing a drop in performance due to underclocking...fine.
But it will always be a drop in performance.
Undervolting in opposite to underclocking produces no drop in performance but actually a rise in efficiency. (and thats what CPU/GPU development is all about).
Less heat, less battery depletion, same performance.
Why not taking advantage of that by undervolting?
Its free lunch.

simms22 said:
i underclock, sometimes to 1036mhz max, with all 4 cores always on by default(no hotplugging). sure, in a benchmark itll score less, just like i expect to score more when im overclocked. but to the normal user, they would never be able to tell that my phone is only clocked to 1036mhz. meaning the user experience isnt lowered in any way. even intense gpu oriented games dont show that im running underclocked. so when you say it drops the performance, it isnt entirely accurate.
Click to expand...
Click to collapse
I agree with you here. 1036 mhz is a great CPU speed for running the device and most apps. Most games UC the CPU for better battery temp like in PPSSPP. Less temperature throttle and more stable frames per second.
Benchmarks are a difference story though but who cares about those. UC is lag free, and buttery smooth so why not?
Sent from my Nexus 5 using Tapatalk

zz_marcello said:
Sorry, but CPU underclocking means always a drop in CPU performance.
When you compensate this drop in your case by always having all four cores active you produce more heat with the active cores.
(and I estimate it will produce more heat/battery depletion than the original phone settings. (max 2,26Ghz and variable core usage)
When you argue that in general a normal user is not realizing a drop in performance due to underclocking...fine.
But it will always be a drop in performance.
Undervolting in opposite to underclocking produces no drop in performance but actually a rise in efficiency. (and thats what CPU/GPU development is all about).
Less heat, less battery depletion, same performance.
Why not taking advantage of that by undervolting?
Its free lunch.
Click to expand...
Click to collapse
again, sure, if youre benchmarking the performance will drop, yes. but if its something that the user doesnt see or feel, then its irrelevant.
no extra heat is produced. also, i get 5.5-7h screen on time with very heavy use. granted, i use the browser much more than i game, but thats what i use my device for mostly.
when needing the extra performance, or wanting to, i overclock. everybody uses their device differently, has differing needs. i would never say one way is better or worse than the other way.

simms22 said:
again, sure, if youre benchmarking the performance will drop, yes. but if its something that the user doesnt see or feel, then its irrelevant.
no extra heat is produced. also, i get 5.5-7h screen on time with very heavy use. granted, i use the browser much more than i game, but thats what i use my device for mostly.
when needing the extra performance, or wanting to, i overclock. everybody uses their device differently, has differing needs. i would never say one way is better or worse than the other way.
Click to expand...
Click to collapse
You can do everything you are already doing, but also undervolt, and your battery life will increase, without affecting your performance. Your performance will be different than my performance (because I don't underclock), however imperceptible as it may be. So undervolting is still better than not undervolting, even for you.

Using EX kernel 3.27, underclocked to 1.5Ghz, undervolted to "700 min" and using "stock" thermal throttling setting. Rock solid and it barely even gets warm now. Responsiveness and performance is only a touch worse than stock; the only places I really notice any performance reduction is in intensive games and app install times. Battery life is massively improved.

CPU undervolting concept and results

This is an outdated device, but since SD801 is so efficient, I gave it a try.
Warning - undervolting is a risky process. It may constantly crash your device, make it unusable or you can actually lose all of your data. Be aware.
So, after reading various articles about CPU binning concept, I thoroughly examined my device's potential. Note, that every device is different, regarding CPU quality and etc.
Anyways, I am running stock rom with Boeffla kernel. I actually gave up, when my device was getting hot - I don't like that at all. Since thermal throttling is really aggresive, I wanted to get away from that completely. And I did.
Currently my phone is heavily undervolted (by 0.1V to be exact) and to be honest, CPU temperatures now never ever exceed 50ºC. With stock voltages, I could easily reach 80ºC.
Anybody else tried doing undervolting? Share your experiences. I would greatly appreciate that.

what is the benefit of it?
does it give a better battery life............?

binadam23 said:
what is the benefit of it?
does it give a better battery life............?
Click to expand...
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The only real benefit of undervolting is to reduce temps. Even so it isn't recommended because of the risk of instabilities.
Saber.

Saber said:
The only real benefit of undervolting is to reduce temps. Even so it isn't recommended because of the risk of instabilities.
Saber.
Click to expand...
Click to collapse
lower temperature = lower power consumption = better battery life.

Kriomag said:
lower temperature = lower power consumption = better battery life.
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Click to collapse
Not necessarily. In my experience in kernels, undervolting only brings marginal power savings. Most battery drain is from open apps and from the display.
Saber.

Wake locks play a big role too I always turn off as may features as I can on my s5 verizon and settings database editor App to turn off more features than normally possible
Sent from my iPhone using Tapatalk

Saber said:
Not necessarily. In my experience in kernels, undervolting only brings marginal power savings. Most battery drain is from open apps and from the display.
Saber.
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Not exactly marginal from my experience. It also depends on which frequency CPU is running. At higher clocks, lower power consumption is more noticeable than on lower frequencies.

airidosas252 said:
Not exactly marginal from my experience. It also depends on which frequency CPU is running. At higher clocks, lower power consumption is more noticeable than on lower frequencies.
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Well, that's not quite the same as what I was saying.
Different CPU frequencies use different current levels which will affect the power draw. So in this case, it will affect the battery savings. Whereas undervolting alone doesn't bring much of a difference due to the already efficient design of our SOC (well, at least in my case ).
Saber.

Undervolting -> Lower Temp -> Less Throttling -> Better Performance with slightly better battery life.
Sent from my SM-G900F using XDA Labs

Throttling is really noticeable with stock voltages. Play some games for a while and you'll start to feel that phone is getting slower and hotter. Not the case anymore after undervolting. If your phone can handle upto 0.1V undervolt, then your SOC is in good shape.

Wlld1 said:
Undervolting -> Lower Temp -> Less Throttling -> Better Performance with slightly better battery life.
Sent from my SM-G900F using XDA Labs
Click to expand...
Click to collapse
i can confirm this, i feel my phone is really snappy now and slightly worm, not hot anymore
I use 300-2000Mhz and heavy UV 620-850V. I also use "use_spi_crc=0".
After phone reboot on stock i get 80'C (cpu tem module in xposed) and on my settings it is not reaching 60'C
What about battery life? it needs long testing, i can assume that its slightly better because less energy is converted in to heat

There seems to be some misconception on undervolting.
In theory undervolting should translate to better battery life. However....
Real world results tell a different story as it shouldn't really make much difference at all. For example, not all S5 phones run the same voltage tables (different CPU quality require more/less voltage), yet they achieve the same battery life. So what voltage was set by the manufacturer (Samsung) is already the optimum voltage.
You will definitely achieve better thermals after undervolting, but in the custom kernel world, most kernel developers will not be able to provide help in the case of instabilities. Some kernel developers may not even provide undervolting support because there just isn't a great enough benefit other than improving thermals.
Saber.

What about undervolting Busses, Image processing System, MMC Memory, GPU and CPU?
I`ve got the exynos variant of the S5. I undervolted to -85 all of that stuff and the phone now doesn't heat at all and battery life isn't that amazing but it is noticeably better

Rudy1967 said:
What about undervolting Busses, Image processing System, MMC Memory, GPU and CPU?
I`ve got the exynos variant of the S5. I undervolted to -85 all of that stuff and the phone now doesn't heat at all and battery life isn't that amazing but it is noticeably better
Click to expand...
Click to collapse
I'm using the snapdragon variant with boeffla kernel so only the CPU is allowed to be undervolted.
Undervolting other components alongside the CPU will make a more noticeable difference in terms of battery savings. It still isn't recommended by many kernel devs as these other components are more sensitive to slight voltage changes (including the bus).
Saber.

Saber said:
I'm using the snapdragon variant with boeffla kernel so only the CPU is allowed to be undervolted.
Undervolting other components alongside the CPU will make a more noticeable difference in terms of battery savings. It still isn't recommended by many kernel devs as these other components are more sensitive to slight voltage changes (including the bus).
Saber.
Click to expand...
Click to collapse
Yeah it actually makes a slight difference in battery life, But I don't think anyone should go below these values since I started to get Screen of death and all that kinda stuff that happens when phones are very undervolted haha
If there's a kernel that allows users of Snapdragon phones to undervolt that hardware, I really recommend you to do it, it really helps battery's performance if you need that extra hour of Screen On time
Now, all of this changes are not recommended cause there could be problems with your phones if you're not sure bout the parameters you're playing with.

does anybody else have problem with gpu oc ? no matter what settings i use there is no performance increase at all, its like the 600Mhz is permanent even when all monitoring programs show 700-800Mhz :/ I have tested gpu many times using 3dmark - always the same fps (600-800Mhz). With 200Mhz increase in frequency it should be significant increase in fps!