Develop Bugs

[Q] HAVS + CPU Control & [Q] Battery Applications

I have a HAVS kernel (Net's 4.2.2 SBC CFS Aggressive HAVS) and as I understand it any sort of CPU Tweaking application will cause conflict and probably a system crash, correct?
Also, can some recommend me any applications that compliment Juice Defender well. I have Juice Plotter already. I am looking for an aggressive auto task killer that's customizable along with any other suggested applications. Thank you!

A system crash is a possibility but they will basically just counteract each other and either make your battery life worse or give a performance hit.
SetCPU helps dynamically underclock/overclock based on certain scenarios. You can set what scenarios you want. Another option is AutoKiller. It isn't Auto Task Killer. Its a different application. Not quite sure how this works but you can research it. However Froyo does a good job managing most applications.
But if you are looking for customization I would go with SetCPU and AutoKiller

Thank's however since I'm running a HAVS kernel I won't use SetCPU. However I will look into Autokiller. Thanks

Vulf said:
Thank's however since I'm running a HAVS kernel I won't use SetCPU. However I will look into Autokiller. Thanks
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Click to collapse
o.o a ton of people use set cpu with havs... its not setting voltages... its setting the cpu speed...

I just installed setcpu and ran it. My phone crashed about 10 seconds after I allowed root access. Tried twice more with same results.

aimbdd said:
o.o a ton of people use set cpu with havs... its not setting voltages... its setting the cpu speed...
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Click to collapse
Its the governors that conflict. Not sure on the exact technical specifics but think of it like OCing a comp.
Some mobos have dynamic OCing. They adjust voltages based on CPU draw. If SetCPU sets CPU speed but HAVS reduces voltage... it would cause a crash. Its always better to have one thing deal with both CPU and voltage.
I'm not a full blown expert with kernels and how they function. All I know is to not mess around with SetCPU + HAVS kernels. It was always unstable or a massive battery drain for me based on my testing.

sekigah84 said:
Its the governors that conflict. Not sure on the exact technical specifics but think of it like OCing a comp.
Some mobos have dynamic OCing. They adjust voltages based on CPU draw. If SetCPU sets CPU speed but HAVS reduces voltage... it would cause a crash. Its always better to have one thing deal with both CPU and voltage.
I'm not a full blown expert with kernels and how they function. All I know is to not mess around with SetCPU + HAVS kernels. It was always unstable or a massive battery drain for me based on my testing.
Click to expand...
Click to collapse
Setcpu does not do anything that a user with root access and terminal emulator can't. Setcpu does not actively do anything related to cpu speed or voltage in way shape or form. What setcpu does do is set the min and max speed the cpu can scale to and the parameters specific to the governor (up-threshold for one).
The governors also don't conflict with setcpu because setcpu does not do anything that a governor does.
The only things setcpu does is allow you to specify what governors and cpu speeds to use during screen on/off, charging, and battery levels through the use of a gui.
Technically setcpu does not interfere with havs its the settings that cause the issues. Again, what setcpu does any root user with te can do. If you issue the wrong settings in te and your device "crashes" is the user going to blame the settings or te? With the way some people are they would probably claim te interferes with havs instead of realizing that the setting combo they issued is not stable.
Setcpu is a great gui to tweak cpu parameters but don't confuse it with an app that actually controls the dynamic cpu frequency scaling or its voltages.

lovethyEVO said:
Setcpu does not do anything that a user with root access and terminal emulator can't. Setcpu does not actively do anything related to cpu speed or voltage in way shape or form. What setcpu does do is set the min and max speed the cpu can scale to and the parameters specific to the governor (up-threshold for one).
The governors also don't conflict with setcpu because setcpu does not do anything that a governor does.
The only things setcpu does is allow you to specify what governors and cpu speeds to use during screen on/off, charging, and battery levels through the use of a gui.
Technically setcpu does not interfere with havs its the settings that cause the issues. Again, what setcpu does any root user with te can do. If you issue the wrong settings in te and your device "crashes" is the user going to blame the settings or te? With the way some people are they would probably claim te interferes with havs instead of realizing that the setting combo they issued is not stable.
Setcpu is a great gui to tweak cpu parameters but don't confuse it with an app that actually controls the dynamic cpu frequency scaling or its voltages.
Click to expand...
Click to collapse
Ahh there. someone more knowledgable then me explains it perfectly.
I've run set cpu plus haves kernel for the last month... as have almost everyone using savagedzen.. thats what they recommend. If it was causing issues i am sure we would know by now. 100%stable... 0 random reboots! (well... accept for when i didn't follow directions xD)

aimbdd said:
Ahh there. someone more knowledgable then me explains it perfectly.
I've run set cpu plus haves kernel for the last month... as have almost everyone using savagedzen.. thats what they recommend. If it was causing issues i am sure we would know by now. 100%stable... 0 random reboots! (well... accept for when i didn't follow directions xD)
Click to expand...
Click to collapse
I believe you and am not discrediting you but how come when I run SetCPU on a kernel with HAVS, it crashes? (Tried 4.3.1 and 4.2.2.) I moved the maximum value from the default 944 by maybe one or 2 notches up and the device freezes and crashes. Maybe Netarchy's kernels aren't compatible with CPU Tweaking programs? Anyone out there running a Netarchy Kernel w/ HAVS + SetCPU successfully?

Vulf said:
I believe you and am not discrediting you but how come when I run SetCPU on a kernel with HAVS, it crashes? (Tried 4.3.1 and 4.2.2.) I moved the maximum value from the default 944 by maybe one or 2 notches up and the device freezes and crashes. Maybe Netarchy's kernels aren't compatible with CPU Tweaking programs? Anyone out there running a Netarchy Kernel w/ HAVS + SetCPU successfully?
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Click to collapse
Again, it is not setcpu it is your settings. You said you moved the slider "one or two notches up" (overclock) from the default 944? The evos default max is 998. Either way, with what you said you are overclocking and your device cannot handle the overclocked speed.
Like I said, you can do the exact same thing that setcpu does through terminal emulator. Instead of blame setcpu you should observe the speed/governor combo you are using.
I can oc my evo to 1.26 on my personal kernel without it rebooting on certain governors but on others it would reboot randomly and I don't set cpu parameters through setcpu, I use te, init scripts, and tasker.

lovethyEVO said:
Setcpu does not do anything that a user with root access and terminal emulator can't. Setcpu does not actively do anything related to cpu speed or voltage in way shape or form. What setcpu does do is set the min and max speed the cpu can scale to and the parameters specific to the governor (up-threshold for one).
The governors also don't conflict with setcpu because setcpu does not do anything that a governor does.
The only things setcpu does is allow you to specify what governors and cpu speeds to use during screen on/off, charging, and battery levels through the use of a gui.
Technically setcpu does not interfere with havs its the settings that cause the issues. Again, what setcpu does any root user with te can do. If you issue the wrong settings in te and your device "crashes" is the user going to blame the settings or te? With the way some people are they would probably claim te interferes with havs instead of realizing that the setting combo they issued is not stable.
Setcpu is a great gui to tweak cpu parameters but don't confuse it with an app that actually controls the dynamic cpu frequency scaling or its voltages.
Click to expand...
Click to collapse
Couldn't have said it better. The common misconception around these parts is that SetCPU has some negative effect on kernels with HAVS and this is just untrue.

Maybe I'm getting some terrible luck. I've always gotten negative results from using both SetCPU and HAVS. Tried different settings and recommended settings from others. As well as trying to tweak it myself. Not working so I just removed it and HAVS worked better on its own.
Sorry for the misinformation.

sekigah84 said:
Maybe I'm getting some terrible luck. I've always gotten negative results from using both SetCPU and HAVS. Tried different settings and recommended settings from others. As well as trying to tweak it myself. Not working so I just removed it and HAVS worked better on its own.
Sorry for the misinformation.
Click to expand...
Click to collapse
The common practice with setcpu is to use it to underclock when sleeping. Depending on the governor you use (besides powersave) you are actually causing the cpu to struggle when completing tasks if you limit the max to 245 for example. During sleep if it needs to perform a task and that task would normally complete in 1 second at 998 mhz imagine how much longer it would take if it was capped at 245.
I have had better results not underclocking while sleeping. I would suggest using setcpu to specify to use the conservative governor when sleeping, ondemand/interactive/smartass when screen on (depending on which one you want), and interactive/ondemand while charging without under/overclocking at all and using the default freqs (245 - 998). I'm certain you would be surprised at how your evo behaves after that.

I don't know though... if race to idle applied here why would phone manufacturers ever under clock their phone? It kind of confuses me. Rti applies to computers but not phones? doesn't make sense.

aimbdd said:
I don't know though... if race to idle applied here why would phone manufacturers ever under clock their phone? It kind of confuses me. Rti applies to computers but not phones? doesn't make sense.
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Click to collapse
My last post may have been a bit confusing so I will clarify. When I said underclock I was referring to the practice of capping the max freq to 245 which is what most people do. If you cap the freq at 245 you are essentially underclocked all the time and would cause your cpu to work harder.
The evo underclocks automatically when the cpu load is low enough (idle for example) to save on power, reduce temps, and to basically keep the system running. But I would assume that most of us who have used setcpu have seen how lousy the evo runs when it can't scale up (locked at 245) when using the evo. The governors will underclock the cpu on their own if the device reports it does not need the higher freqs and this occurs during sleep/screen off as well.

Ugh this is quite frustrating. Perhaps it's the current kernel I'm using that's the problem?

Vulf said:
Ugh this is quite frustrating. Perhaps it's the current kernel I'm using that's the problem?
Click to expand...
Click to collapse
Have you done testing to make sure your phone plays well with the more aggressive kernel? If using SetCPU is causing your phone to reboot then you may want to adjust your overclock, switch to the less aggressive kernel, or update to the newest netarchy SBC powered kernel; 4.3.2.

freeza said:
Have you done testing to make sure your phone plays well with the more aggressive kernel? If using SetCPU is causing your phone to reboot then it you may want to adjust your overclock, switch to the less aggressive kernel, or update to the newest netarchy SBC powered kernel; 4.3.2.
Click to expand...
Click to collapse
I'm not sure how I would go testing my kernel? I mean I've been using it since yesterday morning and there haven't been any FC's/phone crashes or anything strange so I guess the aggressive HAVS works well with my phone. I'll try upgrading to 4.3.2. I'm assuming it works fine for you?

freeza said:
Have you done testing to make sure your phone plays well with the more aggressive kernel? If using SetCPU is causing your phone to reboot then it you may want to adjust your overclock, switch to the less aggressive kernel, or update to the newest netarchy SBC powered kernel; 4.3.2.
Click to expand...
Click to collapse
This.
Very sound advice and yes some evos can't undervolt as well as others. Always remember too that the stock kernel for the evos use CFS. If you are using a bfs kernel that could also cause issues. Some evos run better with bfs versus cfs but it's really going to come down to the amount of time you want to put into testing and confirming what your evo likes.

Vulf said:
I'm not sure how I would go testing my kernel? I mean I've been using it since yesterday morning and there haven't been any FC's/phone crashes or anything strange so I guess the aggressive HAVS works well with my phone. I'll try upgrading to 4.3.2. I'm assuming it works fine for you?
Click to expand...
Click to collapse
Yeah, it does. How far are you trying to overclock before your phone freezes/reboots?

[Q] Calk's Preset Profiles to save battery question?

Notes about Battery Saver script
Can be used with kernels that have init.d support
It completely eliminates the need for an application to set CPU speeds or profiles
Easily customizable if you use a text editor(scripts located in /system/etc/init.d)
It will set Max CPU speed to 500MHz & Min CPU speed to 200MHz when a sleep
If SetCPU, Overclock Widget, Android Overclock or QuickClock Advanced Overclock are detected, the script is ignored, so it will not affect them
Preset profiles are:
1.2GHz - 100-85%
1.0GHz - 84-36%
800MHz - 35-0%
And just an FYI, even at 800MHz, the phone still operates very well & smooth but the battery saving are the real benefit
Click to expand...
Click to collapse
Does this mean that if I don't use Set CPU or any app that undervolt it, the phone will AUTOMATICALLY drop the CPU speed according to my battery level:
1.2GHz - 100-85%
1.0GHz - 84-36%
800MHz - 35-0%
Another word, it will automatically drop CPU speed to 800 MHZ when my battery level is 35-0% in order to save battery?

It won't "Drop" the CPU speed, it will lower the Maximum speed the CPU is allowed to ramp up to.

Drumrocker said:
It won't "Drop" the CPU speed, it will lower the Maximum speed the CPU is allowed to ramp up to.
Click to expand...
Click to collapse
So if I am not doing CPU intensive stuff and just play simple games, email, web surfing phone call, then I am not going to see battery improvement since my CPU probably don't ramp past 800MHZ anyway when I am just doing simple stuff.?

Calk's ROM undervolts the CPU at all speeds so that in itself should help a little with battery life. But you are correct, if you are not doing CPU intensive tasks the CPU probably isn't spending much time at the higher speeds.
There is an app called CPUSpy which shows how much time the CPU has spent in each frequency state.

Your phone will ramp up to 1200 mhz more than you think. When it loads a webpage, it will ramp up to 1200, when it's loading your "simple" game, it will max out for a bit, etc.
It might not stay there for very long, but still. The nice thing about Calkuins rom is that even at 800 mhz, the phone is super smooth and lag free. In fact I just turn setcpu down to 800 all the time.

Let me research setcpu and play around with it. Thanks again for the quick answers.

clamknuckle said:
Your phone will ramp up to 1200 mhz more than you think. When it loads a webpage, it will ramp up to 1200, when it's loading your "simple" game, it will max out for a bit, etc.
It might not stay there for very long, but still. The nice thing about Calkuins rom is that even at 800 mhz, the phone is super smooth and lag free. In fact I just turn setcpu down to 800 all the time.
Click to expand...
Click to collapse
The way Calkulin's rom scripts are setup, setcpu gets reset on every reboot, even if you have it set to boot settings. The scripts installed will still take priority and the old rules apply, just to let you know. So you would have to set setcpu every boot for it to work, that or remove the scripts.
Sent from my SPH-D710 using xda premium

Team era... Does the same idea apply to the blazer 2.0 battery saving script? or does tegrak break it?
Sent from my SPH-D710 using xda premium

I havnt opened that rom, but Im gonna say the same applies, I remove those scripts, 2 will affect the cpu state.
edit, let me clarify, the scripts take prority, even if the app makes a script for init.d, the original script will take over on a reboot. So the script breaks tegrak, setcpu, and voltage control unless you set the app on every reboot.

I am running Calks 2 and desperado kernel. I notice when using setcpu, if you have it set on boot, it will override calks script.
His script does work well on saving battery life though. I ran oc'd while at 20% and still had 1700mhz blazing on performance gov.
I'd still use Calks script over setcpu or tegrak only due to the fact im too sporatic with my phone use to create optimal profiles to fit the way and when i need to use the device.

mindgrind said:
I am running Calks 2 and desperado kernel. I notice when using setcpu, if you have it set on boot, it will override calks script.
His script does work well on saving battery life though. I ran oc'd while at 20% and still had 1700mhz blazing on performance gov.
I'd still use Calks script over setcpu or tegrak only due to the fact im too sporatic with my phone use to create optimal profiles to fit the way and when i need to use the device.
Click to expand...
Click to collapse
Actually in my own testing setcpu will not override the scripts, the slider may stay the same, but trust me, it goes back to 800 (or 1200 over 86%batt), Ive tested it several times. If you want proof Ill tell you how to figure it out. I know Im not respected yet, but I am someone that is known under another name that is highly respected, so, take it as you will.
Sent from my SPH-D710 using xda premium

Era, what's your suggestion for keeping the battery saving scripts running and getting a 1500 ish over clock when needed... something that can do both without having to physically change setcpu everytime. I basically want to permanently over clock to 1.5 and still save as much battery as possible when i have the screen off or it is charging. Idk if setcpu profiles work on this phone because i know they did not work correctly on the galaxy s. And one final question... what voltages do u run at what speeds on the "desperado" kernel to undervolt efficiently?
Sent from my SPH-D710 using xda premium

TeamERA said:
Actually in my own testing setcpu will not override the scripts, the slider may stay the same, but trust me, it goes back to 800 (or 1200 over 86%batt), Ive tested it several times. If you want proof Ill tell you how to figure it out. I know Im not respected yet, but I am someone that is known under another name that is highly respected, so, take it as you will.
Sent from my SPH-D710 using xda premium
Click to expand...
Click to collapse
ERA. I wasn't looking to say that you were wrong in any way shape or form. I would be interested to know how you seen this as I am still in the beginning phases of learning the android system. I do plan on writing my own kernal/roms but I was actually sharing what my logical thought process would have been given the apps and system info I had avail.
I have a little ways to go in understanding the structure and FS of droid. Time is everyones enemy. Thanks for the correction again!

I havnt opened that rom, but Im gonna say the same applies, I remove those scripts, 2 will affect the cpu state.
edit, let me clarify, the scripts take prority, even if the app makes a script for init.d, the original script will take over on a reboot. So the script breaks tegrak, setcpu, and voltage control unless you set the app on every reboot.

I'm currently running Calkulin's rom v2.5, and even at 41% battery I notice the cpu still hits 1.2 Ghz. Is his script activated by default or am I overlooking something? I also have nothing like setcpu installed.

First time undervolting

Ok so im getting 12 hours tops running blazer 3.7 rom with the el29 1.4.0 gunslinger kernel and ek02 baseband
I have set cpu all I have done so far is just make the profiles. I need some help its my first time trying the undervolting I want that 16 hour plus battery life
Sent from my HTC Glacier using XDA App

Why not just try -25mV for each frequency that you're using? Test it for a few days. Then try -50mV, repeat test, and compare performance differences.
If you're overclocking, undervolting can freeze or boot loop your device

Switch over to Rogue Stock EL29 and undervolt + underclock using Tegrak. I guarantee you'll get 16+. Right now I'm getting 24+ hours with these settings:
CPU Scaling: 200-800Mhz
Internal Voltage: -75mV from default.
Core Voltage: -75mV from default.
GPU Level 0 Frequency: 200Mhz
GPU Level 0 Voltage: 850mV
GPU Level 1 Frequency: 100Mhz
GPU Level 1 Voltage: 750mV
Tweaks: cfq changed to noop
System will constantly reboot if you use Tegrak with Gunslinger so don't do it. Just get Rogue Stock EL29.

R0CKSTAR3N3RGY said:
Switch over to Rogue Stock EL29 and undervolt + underclock using Tegrak. I guarantee you'll get 16+. Right now I'm getting 24+ hours with these settings:
CPU Scaling: 200-800Mhz
Internal Voltage: -75mV from default.
Core Voltage: -75mV from default.
GPU Level 0 Frequency: 200Mhz
GPU Level 0 Voltage: 850mV
GPU Level 1 Frequency: 100Mhz
GPU Level 1 Voltage: 750mV
Tweaks: cfq changed to noop
System will constantly reboot if you use Tegrak with Gunslinger so don't do it. Just get Rogue Stock EL29.
Click to expand...
Click to collapse
Can you list your CPU scaling at each level? Thanks

Make your self an overclock profile and copy paste this into it in through a text editor:
level=5
frequency=1200000,1000000,800000,500000,200000
core_voltage=1150,1100,1000,900,850
int_voltage=1000,975,950,925,900
scaling_governor=ondemand
scaling_min_freq=200000
scaling_max_freq=800000
author=Chris Brinzo
If you don't know where to find your overclock profiles, go to where your applications install, such as sdcard, the directory will be sdcard/Tegrak/overclock/ then the file will be <profile name>.oc
Use something like file expert to open it as a text, then simply copy paste.
**This is a custom profile not to the specs I listed before, it is very good for battery life**

R0CKSTAR3N3RGY said:
Make your self an overclock profile and copy paste this into it in through a text editor:
level=5
frequency=1200000,1000000,800000,500000,200000
core_voltage=1150,1100,1000,900,850
int_voltage=1000,975,950,925,900
scaling_governor=ondemand
scaling_min_freq=200000
scaling_max_freq=800000
author=Chris Brinzo
If you don't know where to find your overclock profiles, go to where your applications install, such as sdcard, the directory will be sdcard/Tegrak/overclock/ then the file will be <profile name>.oc
Use something like file expert to open it as a text, then simply copy paste.
**This is a custom profile not to the specs I listed before, it is very good for battery life**
Click to expand...
Click to collapse
i noticed it said TEGRAK in that field...so this wouldnt work on gunslinger and setcpu? just wondering...cause im looking into this aswell

I'm not entirely sure if it would work with setcpu. I don't know what kind of data it uses.
This is for Tegrak only, as far as I know.
Tegrak will not work on Gunslinger, I use it on Rogue Stock EL29.
This profile for Tegrak delivers excellent battery life while still remaining smooth and stable. As long as you don't murder your phones battery life with applications and data you should get 24 hours + with moderate use.

R0CKSTAR3N3RGY said:
I'm not entirely sure if it would work with setcpu. I don't know what kind of data it uses.
This is for Tegrak only, as far as I know.
Tegrak will not work on Gunslinger, I use it on Rogue Stock EL29.
This profile for Tegrak delivers excellent battery life while still remaining smooth and stable. As long as you don't murder your phones battery life with applications and data you should get 24 hours + with moderate use.
Click to expand...
Click to collapse
alright, im gonna do a nandroid in a bit (im currently on a perfect setup lol) then flash back to stock EL29, then grab tegrak and try this. so i just make a profile on tegrak..go into a root explorer and edit with the data you put up and what? simple copy and paste?

Yes, simply copy and paste, just tested it out to confirm it will work. Once you copy- paste the data you need to reapply the profile in Tegrak. In order for the profile to apply every start up you will need the full version of Tegrak.

R0CKSTAR3N3RGY said:
Yes, simply copy and paste, just tested it out to confirm it will work. Once you copy- paste the data you need to reapply the profile in Tegrak. In order for the profile to apply every start up you will need the full version of Tegrak.
Click to expand...
Click to collapse
Thanks a lot man! Im on calks ROM...and this tegrak setup you recommended and so far sooo good. will update and see if i can get 24hrs out of it!

thanks for the help guys im undervolted -50 using set cpu and yesterday i pulled 12 hours under really heavy use that was with 4 hpurs of screen on time and listen to music all day at work. i been off the charger now for a hour and only lost 3% battery so far but thanks guys dor the help
Sent from my SPH-D710 using XDA App

R0CKSTAR3N3RGY said:
Yes, simply copy and paste, just tested it out to confirm it will work. Once you copy- paste the data you need to reapply the profile in Tegrak. In order for the profile to apply every start up you will need the full version of Tegrak.
Click to expand...
Click to collapse
in order to set that profile it asks to load module...but now all of a sudden it wont.. why? now i cant set that profile..i have the free version.

Carbajal3009 said:
in order to set that profile it asks to load module...but now all of a sudden it wont.. why? now i cant set that profile..i have the free version.
Click to expand...
Click to collapse
Are you pressing load overclock module before you apply it?
Or is there some form if error?
EDIT: Sorry just realized you MUST have the full version to set profiles. (99% Sure of that one)

R0CKSTAR3N3RGY said:
Are you pressing load overclock module before you apply it?
Or is there some form if error?
EDIT: Sorry just realized you MUST have the full version to set profiles. (99% Sure of that one)
Click to expand...
Click to collapse
oh.... well that just blows..any other ideas? have you tried setcpu?

I'm sure you can find the full version of Tegrak somewhere.
I tried SetCPU with Gunslinger and I wasn't a fan. Never got the battery life that I did with Tegrak.

R0CKSTAR3N3RGY said:
I'm sure you can find the full version of Tegrak somewhere.
I tried SetCPU with Gunslinger and I wasn't a fan. Never got the battery life that I did with Tegrak.
Click to expand...
Click to collapse
Ya I tried that... it trys to check the license before I use it...

[Noob Guide] What is and How to Undervolt

Hello, i wanna share my experience undervolting.
For people who dont know what undervolting is, its the power or energy that the battery send to the CPU with determinate clock speed.
For example:
384 Mhz is the lowest frequency of our CPU, it has a 800mv volt in the stock ROM with stock kernel.
So in theory, the battery send 800mv to the CPU when it runs at 384 Mhz.
The effect of undervolt the CPU is bassically get more battery life and at the same time reduce the temperature of the phone.Less energy send less battery used and less hot phone in our hands.
How to Undervolt
Im running Stock ROM with Ruby Kernel stable.
For undervolt you need a kernel that support it, you can do it in all rom if the kernel support that.
If you want to Undervolt, i recommend you to use Trickster MOD.
You can Undervolt maybe -50mv all frequencies and see how it goes. Some people can even in best cases undervolt -200 mv. But you need patience to test slowly.
DONT TICK SET AT BOOT IF NOT TESTED.
That why you cant:
For example if you undervolt -100mv and if not stable, and you have set at boot ticked, it will freeze the screen and after reboot it will happen again.
After you set the mv for undervolt, download from play store CPU stability test and run it.
It will test all CPU frequencies to see if it is stable.
If you dont get any SoD, congratulations its stable.
My undervolt settings are -100 or in some cases -75 mv and very stable. My battery temp is 30 C°.

Thank you very much
Sent from my LG-E975 using XDA Premium 4 mobile app

What is needed to undervolt?

Thanks for the info. What are your battery stats after undervolting? How does it suffer other operations of our mobile like browsing or gaming etc ?
Sent from my LG-E975 using xda app-developers app

You need to first make a backup, install a custom kernel, install trickster mod, and from there apply what this discussion is talking about. Good luck!
Sent from my Nexus 5 using xda app-developers app

lfuentes said:
What is needed to undervolt?
Click to expand...
Click to collapse
Bootloader unlocked with freegee and some kernel for your rom that supports undervolt.

nch26 said:
Bootloader unlocked with freegee and some kernel for your rom that supports undervolt.
Click to expand...
Click to collapse
And after that? Some specific app?

lfuentes said:
Some specific app?
Click to expand...
Click to collapse
Depends on the kernel. I am using Trickster Mod with Viper ZVC kernel. There are other control apps available -- some of them are kernel-specific, some are more universal (Kernel Tuner, Android Tuner, System Tuner, etc.). Look in your kernel's thread -- the developer usually tells which control app(s) to use with it.

nch26 said:
Hello, i wanna share my experience undervolting.
For people who dont know what undervolting is, its the power or energy that the battery send to the CPU with determinate clock speed.
For example:
384 Mhz is the lowest frequency of our CPU, it has a 800mv volt in the stock ROM with stock kernel.
So in theory, the battery send 800mv to the CPU when it runs at 384 Mhz.
The effect of undervolt the CPU is bassically get more battery life and at the same time reduce the temperature of the phone.Less energy send less battery used and less hot phone in our hands.
How to Undervolt
Im running Stock ROM with Ruby Kernel stable.
For undervolt you need a kernel that support it, you can do it in all rom if the kernel support that.
If you want to Undervolt, i recommend you to use Trickster MOD.
You can Undervolt maybe -50mv all frequencies and see how it goes. Some people can even in best cases undervolt -200 mv. But you need patience to test slowly.
DONT TICK SET AT BOOT IF NOT TESTED.
That why you cant:
For example if you undervolt -100mv and if not stable, and you have set at boot ticked, it will freeze the screen and after reboot it will happen again.
After you set the mv for undervolt, download from play store CPU stability test and run it.
It will test all CPU frequencies to see if it is stable.
If you dont get any SoD, congratulations its stable.
My undervolt settings are -100 or in some cases -75 mv and very stable. My battery temp is 30 C°.
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Thank you, I'm using AK kernel with UKM and Synapse app from google playstore. Using E-975 (intl.). Can you suggest if I should change the global setting or the individual settings for frequencies ? I had recently (soft) bricked my phone by running benchmark at ~1900mhz CPU and 487mhz GPU (like a villain, I know. Re-connected battery to save it... phew..). I'm really cautious now and I just want it to be less hot and save some battery, that's all. Any guidance would be really appreciated... thanks

Claureid said:
Thank you, I'm using AK kernel with UKM and Synapse app from google playstore. Using E-975 (intl.). Can you suggest if I should change the global setting or the individual settings for frequencies ? I had recently (soft) bricked my phone by running benchmark at ~1900mhz CPU and 487mhz GPU (like a villain, I know. Re-connected battery to save it... phew..). I'm really cautious now and I just want it to be less hot and save some battery, that's all. Any guidance would be really appreciated... thanks
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I dont have anymore this phone because some people stole my phone like 1 year ago. Sorry.

Oh okay, sad loss....

why cant i underclock the CPU?

Every time I try to underclock the CPU as soon as I leave the app the sliders go back to where they were originally. Even after applying on boot. Am I doing something wrong?

BakedOnSomeSour said:
Every time I try to underclock the CPU as soon as I leave the app the sliders go back to where they were originally. Even after applying on boot. Am I doing something wrong?
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Since you've given virtually no information, I will assume that your phone is unrooted and/or running with the stock kernel. You will need to address both to be able to underclock.

Because underclocking is silly.

Wakamatsu said:
Since you've given virtually no information, I will assume that your phone is unrooted and/or running with the stock kernel. You will need to address both to be able to underclock.
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I am rooted and running elementalX kernel

BakedOnSomeSour said:
I am rooted and running elementalX kernel
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I'm not running EX. Does it use init.d or config script? Those may overwrite whatever method you're using to underclock at boot.

Underclocking-saving battery
Is a BIG LYE
CPU will not use full power (max freq) when not need.
Dont forget what is Mhz (how MUCH things CPU can do in what TIME) the only deffrent bettwen underclocked and overclocked is TIME.312Mhz will do something in 5 mins,but 2 Ghz will do it in 1 second. It just do faster,but battery use is same,count yourself

1. You warmed up a dusty thread.
2. Battery-work isn't simply product of time and frequency: longer low tasks eats fewer capacity than shorter peak ones.