Database Info

400Mhz at -200mV on top of -50mV?

So I'm not sure if this 4th G2x I received is a total beast or SetCPU is just f'ing with me, but I'm cruising at -200mV on top of the already undervolted Faux CM7 kernel.
The phone has absolutely no problems and it just keeps going.
Here's my setup:
1000Mhz Max 950 mV Current 925 mV (-25 mV)
800Mhz Max 850 mV Current 750 mV (-100 mV)
500Mhz Max 800 mV Current 650 mV (-150 mV)
400Mhz Max 770 mV Current 570 mV (-200 mV)
PS: Real men type it out
Edit: Poll added!

GideonX said:
So I'm not sure if this 4th G2x I received is a total beast or SetCPU is just f'ing with me, but I'm cruising at -200mV on top of the already undervolted Faux CM7 kernel.
The phone has absolutely no problems and it just keeps going.
Here's my setup:
1000Mhz Max 950 mV Current 925 mV (-25 mV)
800Mhz Max 850 mV Current 750 mV (-100 mV)
500Mhz Max 800 mV Current 650 mV (-150 mV)
400Mhz Max 770 mV Current 570 mV (-200 mV)
PS: Real men type it out
Click to expand...
Click to collapse
i really wonder sometimes if its really UVing with values so high x_X 216 running at 350mV x_X
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I read in another thread by one of the developers (Faux?) that 770 mV is the lowest allowed voltage due to hardware restrictions and that any settings below that do nothing.

GideonX said:
So I'm not sure if this 4th G2x I received is a total beast or SetCPU is just f'ing with me, but I'm cruising at -200mV on top of the already undervolted Faux CM7 kernel.
The phone has absolutely no problems and it just keeps going.
Here's my setup:
1000Mhz Max 950 mV Current 925 mV (-25 mV)
800Mhz Max 850 mV Current 750 mV (-100 mV)
500Mhz Max 800 mV Current 650 mV (-150 mV)
400Mhz Max 770 mV Current 570 mV (-200 mV)
PS: Real men type it out
Click to expand...
Click to collapse
sincest said:
i really wonder sometimes if its really UVing with values so high x_X 216 running at 350mV x_X
Click to expand...
Click to collapse
You guys have amazing chips
The reason for 770mv @ 389/400 MHz is the limitation of ~100mv per "frequency jump" according to Tegra2 documentation. With the FakeShmoo implementation of overclock, we have a total of 8 slots (frequencies) to play with. If I start the lowest frequency let say at 500mv, then the max voltage at the eighth slot can only be ~1200mv. With 1200mv we can OC to 1.2~1.3 GHz, beyond that then it becomes unstable. So in order to get more juice @ higher clocks, we have to start a higher voltage at the low to get more juice at the high end. Of course, naturally, the next question would be why not start with 1000mv to begin with then you can get 1700mv at eighth slot? If we started with more juice at the low end, it would kill the battery 2x or 3x faster. So the current voltage table you see from my kernels is a compromise between battery life and OC Hope this clears it up a bit.

faux123 said:
You guys have amazing chips
The reason for 770mv @ 389/400 MHz is the limitation of ~100mv per "frequency jump" according to Tegra2 documentation. With the FakeShmoo implementation of overclock, we have a total of 8 slots (frequencies) to play with. If I start the lowest frequency let say at 500mv, then the max voltage at the eighth slot can only be ~1200mv. With 1200mv we can OC to 1.2~1.3 GHz, beyond that then it becomes unstable. So in order to get more juice @ higher clocks, we have to start a higher voltage at the low to get more juice at the high end. Of course, naturally, the next question would be why not start with 1000mv to begin with then you can get 1700mv at eighth slot? If we started with more juice at the low end, it would kill the battery 2x or 3x faster. So the current voltage table you see from my kernels is a compromise between battery life and OC Hope this clears it up a bit.
Click to expand...
Click to collapse
So there really isn't a hardware limit in place on how low this chip can go?
Sent from my HTC Vision (G2x in disguise)

I'm really starting to wonder if setcpu is busting our chops or not I'm
-100mV on all frequencies starting at 594mhz down to 216mhz on morfics jrcu 6/21 kernel, that can't be right can it is there a way to find out for sure???

for frequency 500mhz or 400mhz I can as low as I want ... 10mVs.. even 0mV. so i dont tihnk its accurate

c19932 said:
for frequency 500mhz or 400mhz I can as low as I want ... 10mVs.. even 0mV. so i dont tihnk its accurate
Click to expand...
Click to collapse
do you have any more than 100mV between frequencies?

Black6spdZ said:
do you have any more than 100mV between frequencies?
Click to expand...
Click to collapse
yes I do. should I not exceed 100mV between each frequency level then? would you happen to know the exact biggest voltage difference allowed between each level?
on another note, if I just leave them at 10mV, will that mean the processor will automatically take the voltage down to the lowest possible, or will it just do nothing but run at stock voltage?

c19932 said:
for frequency 500mhz or 400mhz I can as low as I want ... 10mVs.. even 0mV. so i dont tihnk its accurate
Click to expand...
Click to collapse
Yes, it seems possible to make settings that are not logically possible.
It would be nice if either SetCPU (which I am currently using) or Pimp My CPU would display in either real time or histogram what voltages are actually being used in the same way as they show frequency. Although I suspect this may be impossible due to hardware or this would be already implemented.

Added a poll up top.
I made it so you can vote either above or below -50mV. I'm basing this off the OC/UV kernel from Faux123.
I also skipped everything between 1.0 to 1.5Ghz. I'm going to assume at that speed, UV'ing will be very low.

double post

i actually use 1216max and uv it minus 150 all together so fauxs -50 plus i uv it -100, and my phone still flys and battery life is niceeee, oh and for the min i use 389, -200 on top of fauxs -50 so -250 all together

I am OC/UV up to 1200MHz -75mV on all frequencies below the undervolting built into Trinity JRCU kernel. This is stable and further UV gives me trouble. Your assumption about UV at higher frequencies is appears to be incorrect.
The poll actually confuses me, undervolting > -50 could mean I am not undervolting at all since 0 is greater than -50.

Interesting, I can UV more on the lower Mhz than higher. For example, at 1.0Ghz -50mV is already pushing it. Anything higher and I'll notice FC and random closes on certain apps.
First time polling, I guess there's no edit feature to change up the wording. Sigh.

SetCPU doesn't error check so everyone reporting -150mV and greater probably is incorrect. Remember there is only 800mV allowable from the highest frequency and only 100mV allowable between frequencies. So.. take my phone for instance.. I started at the highest 1.5Ghz frequency and tested -25mV at a time until phone rebooted and then went back up 25mV. This just happens to be 1300mV stable for me. This means the lowest 389Mhz can have at the lowest 500mV "1300mV - 800mV". I set everything -50mV across the board and then focused on 503Mhz since no matter what 389Mhz can only be -100mV lower. I was able to get -75Mv "725mV" stable. Then I was able to run 389Mhz stable at -150mV or 620mV. In actuality it is running 625mV since that is 100mV less than the frequency above it... setting it any lower in SetCPU would STILL only be 625mV regardless.
Also, this poll will be useless for everything but the 1500Mhz frequency as we wouldn't know if the user started with the SV or UV kernel. We need multiple polls with the final voltage eg 1100Mhz @ 1000mV,975mV,950mV
Test with a charger plugged in, I've had reboots with a battery at <50% because it cannot supply the high current draw of 100% cpu usage.

My specific settings are as follows as -?? means nothing because different kernels have a different starting point.
1075 mV @ 1200 MHz
975 mV @ 1100 MHz
875 mV @ 1000 MHz
775 mV @ 594 MHz
675 mV @ 432 MHz
575 mV @ 216 MHz
This is solidly stable having run it for several days without any bad behavior although any further reduction of voltage at 1200 MHz causes significant problems.
Phone: G2X
ROM: CyanogenMod 7.1 RC1
Kernel: Trinity 15 jrcu 06212011
Other relevant: SetCPU

I've gotten even better results with the SV kernel. After testing each speed for stability at lower and lower voltages here are my results:
1408Mhz @ 1175mV
1216Mhz @ 1075mV
1100Mhz @ 975mV
1015Mhz @ 900mV
816Mhz @ 800mV
655Mhz @ 725mV
503Mhz @ 650mV
389Mhz @ 595mV
lose 100Mhz from the UV/OC kernel but I get better UV settings with the SV kernel

Black6spdZ said:
I've gotten even better results with the SV kernel. After testing each speed for stability at lower and lower voltages here are my results:
1408Mhz @ 1175mV
1216Mhz @ 1075mV
1100Mhz @ 975mV
1015Mhz @ 900mV
816Mhz @ 800mV
655Mhz @ 725mV
503Mhz @ 650mV
389Mhz @ 595mV
lose 100Mhz from the UV/OC kernel but I get better UV settings with the SV kernel
Click to expand...
Click to collapse
too bad the lowest my phone can go for 1015mhz and 816mhz are 940 and 840mv respectively

Black6spdZ said:
I've gotten even better results with the SV kernel. After testing each speed for stability at lower and lower voltages here are my results:
1408Mhz @ 1175mV
1216Mhz @ 1075mV
1100Mhz @ 975mV
1015Mhz @ 900mV
816Mhz @ 800mV
655Mhz @ 725mV
503Mhz @ 650mV
389Mhz @ 595mV
lose 100Mhz from the UV/OC kernel but I get better UV settings with the SV kernel
Click to expand...
Click to collapse
We seem to be hitting about the same spot, almost exactly, I can OC to 1400 or 1500 but choose not to push my phone to that extent. I live in a very hot area and don't want to tempt fate.

UV limit reached: wakelocks + SOD + Instant Drop in Indicated Battery Level

(I intended to post this in "general:, not q&a)
SUMMARY: I have been slowly decreasing my voltage. Wednesday, three weird things happened on my phone that never happened before (wakelocks, unintended reboot, instant drop in battery indication).
CONCLUSION: I attribute all three things (wakelocks, reboot, instant drop in battery indication) to reaching an unstable voltage.
DESIRED OUTCOMES (Why am I posting this):
1 - I think I understand what happened, but maybe you guys can point out if I'm mistaken.
2 - Maybe someone else will be interested in seeing voltage limits for my phone (-75mV appears to work, -100mV appears to be too low for me... I guess other Infuses may act differently)
3 - It seems to me that maybe excess UV should be considered when investigating causes of wakelocks (there are many other causes of course). This conclusion is based only on this one experience as reported below. I have heard obviously unintended reboot can be associated with too much UV'ing, but I never heard wakelocks could be associated with UVing. Open to comments.
DETAILS:
I’m using stock GB, rooted, Zen’s Infusion A/1600 kernel, with governor conservative 100-1200millivolts.
I have been decreasing my voltage settings by 25 millivolts every other day over the last week.
Wednesday, I got to 100 millivolts below max on all points (except 1600Mhz, which was 50 millivolts down)
Specifically, my levels on Wednesday were:
100 Mhz: 950mv max – 100mv = 850 millivolts
200 Mhz: 950mv max – 100mv= 850 millivolts
400 Mhz: 1050mv max – 100mv = 950 millivolts
800 Mhz: 1200mv max – 100mv = 1100 millivolts
1200 Mhz: 1275mv max – 100mv = 1175 millivolts
1600 Mhz: 1400mv max – 50mv = 1350 millivolts
Before Wednesday, I had performed stability test (using “stability test” program for about 30 minutes... it sweeps the frequencies I think) at 1600Mhz Fmax while 50 millivolts down and another stability test at 1200 Fmax while 75 millivolts down, both for around 20 minutes, no problems there and no other problems with my phone in the last week since I upgraded to GB. When I decreased to 100 millivolts down I only did a 30-second “stress test” from within setcpu at 1200Mhz. No problems there.
All day Wednesday I was running the conservative governor, with Fmin=100 and Fmax = 1200, cfq io scheduler, UV settings as above (all 100 down except 1600Mhz). I have one setcpu profile that puts the phone to 1600Mhz Fmax when I manually launch "Memento Database" program, but I did not launch that program at all on Wednesday, so I never got above 1200Mhz on Wednesday.
My battery profile for the day Wednesday is shown in attached graphic.
The label “phone awake with screen off” points to a time period approx 2-4pm when my phone was awake with the screen off. I have never seen this happen on my phone before, and I look at this screen pretty regularly.
I used the phone heavily during my hour-long ride home from work from 5pm to 6pm (no problems). I was surfing the internet, reading the news about the Hurricane in New Orleans (not tweaking my phone). Phone worked absolutely perfectly throughout this hour long heavy usage.
First thing on getting home, I connected to wifi and surfed for about 5 minutes. At about 6:10pm, while surfing with my battery level happened to be 47% (as I deduced later), suddenly appeared the black screen with Samsung logo ... phone booted up to normal home screen. I think that’s what you guys call the “screen of death”?
I assume the phone reboot may be my first indication that I’ve reached my limit for UV’ing?
But here’s what concerned me more than the SOD:
Immediately after rebooting, my battery now showed 8% !
How does it go from 47% to 8% that fast? I have several screens from “battery monitor widget” and from the Android battery screen, and they all confirm the battery dropped from 47% to 8% over this very short time period (less than 5 minutes). I also have audible low-battery warnings on my phone (generated by Tasker, a lass with a pretty British lady voice) at levels of 40%, then 30%, then 20%, then 10%. I didn’t get any of those audible warnings prior to this spurious reboot – seems to confirm either this was a real drop in battery, or else my battery signal feeding all my applications (battery monitor widget, Tasker, GB battery profile) somehow went bezerk.
I have a hard time imagining this could be a real drop in battery ....where would the energy go? The phone did not get hot.
Is it possible somehow the phone’s battery calibration got confused?
Attached is a screenshot of battery drop.
The rapid drop from 70% to 50% was when I was using the phone heavily for an hour... I consider that normal.
The vertical drop from 47% to 8% is what is completely unexplainable to me. Although I have seen in the forum reports of battery gage reading unreliably in certain circumstances.
By the way, I put my UV setting back to -75 Wed night, and phone working fine ever since. No wakelocks or other anomolies.
Questions:
1 – Is this what is known as “screen of death”
2 – Has anyone seen that type of rapid battery level decrease?
3 – What do you think caused it.... calibration problem or actual loss of battery? If calibration problem, it’s kind of weird that the voltage increased smoothly during recharge afterwards?
4 – Do you think the phone-awake-with-screen off occurences earlier in the day are related to my UV'ing? I didn't see them before and I haven't seen them since went back to -75mV, suggesting they are caused by UV'ing. But also note the phone worked fine during my hour long drive home after the wakelocks and before the SOD
5 – Do you agree I have probably reached stability limit and should stick with 75 millivolts down instead of 100 (I have been back on 75 again for awhile...no problems)
Attached below is my battery voltage over the course of the day, annotated with the items discussed above.

If you undervolted, your going to run into problems man. Simple as that. If you do anything to your phone not stock these things can and will happen.
Just take is as a fluke and move on. Everyone's phone uv's differently.
Imo what happened is the processor was making lots of errors and corrupted some part about your batteries actual percentage and was a lot lower than was presented to you.
Phone awake while screen on is a wakelock and quite common. Usually an app holds the phone turned on.
Edit: if uv of 75 fixes the problem. Then that definitely us what you should do. Note, benchmarks don't give stability reports. You would need run them for hours before you get accurate assessment.
Sent from my SGH-I997 using xda premium

1 – SOD is when the screen is black and phone won't unlock. Sometimes the volume buttons work. A long press of the power button will usually reboot the phone.
2 – The rapid power drains I've seen have typically been due to the rild process running amok and maxing the cpu. Typically the phone gets hot when this happens. In a SOD situation, you can typically still connect to the phone via ADB. If you can do this, run "adb shell" and then the following command: "top -m 5 -n 1" (spacing emphasized as all spaces are required).
3 – Dunno, but I'm with Elliot: the thing you changed was UV. Back that out and see if the problem goes way.
4 – Awake when screen off is usually related to an app that sets a wakelock and syncs in the background. Use Better Battery Stats to troubleshoot this. If it was UV causing this, I'm not sure why that would be - see #3
5 – FWIW, I never UV below -75... and truth be told I haven't seen a significant savings in battery life with UV, but that's likely because my phone is asleep most of the time...

Thanks for your response Elliot.
I think you interpretted it roughly the same as me except you lean more towards other possible causes of wakelocks unrelated to UV. That is certainly possible and I will keep a close eye on tha (moreso as a reuslt of your comments)
I am moving on with my phone at –75mv and don’t plan any drastic changes as a result of this unless I see more problems, but I also want to treat this as a learning experience. I spent awhile collecting the data and drawing my own conclusions, but wanted to bounce it off the others here for my own long-term learning.
Thanks again.

Thanks Zen, good info as always.

if you UV, i had better luck with higher UV on the top end:
ex: -125 or 150 @ 1600
-100 or 125 @ 1200
-75 or 100 @ etc
Basically, you are limiting power consumption and increasing battery life.
Once you hit the lower limit, your phone will let you know.
If you care to try, and you will have a slower phone:
set cpu max to 800 and then uv -75, -50, -25 stepping down. you will see the difference. it will make calls or mms fine. But you will notice slowdown with web/games/etc

every cpu is different. i've had 2 infuses because my screen broke, i replaced it and the replacement was defective, found another phone for about the price of a replacement screen.
one get's me about -100mv the other was completely stable at -225(maybe more) with stock clocks and -200 overclocked.
one thing that can cause instability is a big voltage differential from low to high especially with on demand governor, it's not only a matter of necessary volts to drive the chip per clock, the rapid fluctuations can cause issues. if you want performance you might want to uv from the top down leaving the lower freqs stock and seeing how much uv it will tolerate at 1600 before you mess with lower clocks, you might get more uv on the upper clocks that way which will reduce heat. if you want battery life then try less or no overclock still going from the top down.
for people that can't reach 1600, or think they can't try to set 1400 and 1600 at the same voltage so the voltage table has a plateau at the top. setting 1200 and 1400 high might smooth the transition to 1600, also try the voltages across the board, there may be a narrow range where the heat and required voltage balance out. i did this with my captivate and got it from 1200 to 1300mhz but 1300 would only work in a narrow 50mv range and 1200 needed to be enabled as well as set to the same voltage. the chip in that phone didn't like overclock at all compared to most infuses but sometimes thats how it goes.

still have wakelocks
if you UV, i had better luck with higher UV on the top end:
Click to expand...
Click to collapse
one thing that can cause instability is a big voltage differential from low to high especially with on demand governor, it's not only a matter of necessary volts to drive the chip per clock, the rapid fluctuations can cause issues.
Click to expand...
Click to collapse
Interesting. Both comments end up suggesting the same strategy to my way of thinking (more UV'ing at top frequencies will create a flatter voltage curve across the range of frequencies). I'll give it some thought when I get back to polishing my uv strategy. Maybe instead of putting all back to -75 I should do something like:
100 Mhz: 950mv max – 75mv = 875 millivolts
200 Mhz: 950mv max – 50= 900 millivolts
400 Mhz: 1050mv max – 75mv = 975 millivolts
800 Mhz: 1200mv max – 100 mv = 1100 millivolts
1200 Mhz: 1275mv max – 75mv = 1200 millivolts
1600 Mhz: 1400mv max – 100mv = 1300 millivolts
...and stick with conservative governor to avoid the big jumps. That way I'd never jump more than 100millivolts (except between 400 and 800 which jumps by 125... but was apparently already a 150mv jump in the stock?). But I'd want to do some testing on the at 1600 to see how it likes the 100mv down, first. Sound reasonable?
========
New subject
An "update" on my phone:
My battery display still shows today that there is quite a lot of time with cpu on and screen off (wakelock) even though now my phone is not undervolted at all today (I removed undervolting to do some testing and haven't put back the uv'ing yet).
I'm heading over to the market to download Better Battery Stats per Zen's suggestion.
Thanks

electricpete1 said:
Interesting. Both comments end up suggesting the same strategy to my way of thinking (more UV'ing at top frequencies will create a flatter voltage curve across the range of frequencies). I'll give it some thought when I get back to polishing my uv strategy. Maybe instead of putting all back to -75 I should do something like:
100 Mhz: 950mv max – 75mv = 875 millivolts
200 Mhz: 950mv max – 50= 900 millivolts
400 Mhz: 1050mv max – 75mv = 975 millivolts
800 Mhz: 1200mv max – 100 mv = 1100 millivolts
1200 Mhz: 1275mv max – 75mv = 1200 millivolts
1600 Mhz: 1400mv max – 100mv = 1300 millivolts
...and stick with conservative governor to avoid the big jumps. That way I'd never jump more than 100millivolts (except between 400 and 800 which jumps by 125... but was apparently already a 150mv jump in the stock?). But I'd want to do some testing on the at 1600 to see how it likes the 100mv down, first. Sound reasonable?
========
New subject
An "update" on my phone:
My battery display still shows today that there is quite a lot of time with cpu on and screen off (wakelock) even though now my phone is not undervolted at all today (I removed undervolting to do some testing and haven't put back the uv'ing yet).
I'm heading over to the market to download Better Battery Stats per Zen's suggestion.
Thanks
Click to expand...
Click to collapse
in my experience that will probably work well. but if the phone is at it's limits with the 1600mhz clock then you might have a specific voltage that it prefers so it's possible it doesn't work into what i was describing. try it, i can't say uv is safe but i haven't broken a phone yet by driving the voltage too low. it just tends to crash and will be fine on the next boot after you clear the settings in my experience so far.

Thanks. I went ahead and made the above changes in voltage. Then I manually rebooted (to allow voltage changes to take effect), went into setcpu to set my max frequency to 1600.
Successful stress test from within setcpu ~ 50 seconds.
Then went to the application named "Stability Test", selected "scaling" (which is supposed to vary the frequency) and has been successfully running the test for 14 minutes (11 successful cpu runs and 75 successful RAM runs). It has been on 1600Mhz the whole time according to the Stability Test display. The battery temperature increased from 37 to 42 pretty quickly then slowed, looks to be stable at 43C now.
Elliot warned above that it takes stability tests hours to find problems and Stability Test documentation mentions something about 5 hours on one frequency to find a problem. But if it's only running at one frequency as it appears from the display (stuck on 1600), I think even after running it for 5 hours I might not be confident that it will ferret out all the problems that might arise while switching frequencies (and I'm not sure I want to leave it running for 5 hours if it's stuck on 1600). I'm not sure exactly what is the purpose of "scaling" mode is, if it doesn't change frequency.
At any rate, I''m going to terminate the test and give it the real-life test now.
I will leave my governor at 100-1600 conservative governor for a few days to help shake out any glitches hiding inside there.
Will let you know if anything goes wonky.
Later on when I'm confident in results, I plan on setting up profiles for 100-400, 100-800, 100-1200, 100-1600 depending on the situation, but will stick with conservative in all cases.
Thanks again.

I wanted to provide an update of testing I have done with UV on my phone. Nothing conclusive for me yet, just a lot of data.
I’ll discuss 5 different UV settings labeled below as 0, A, B, C, D (going from most UV to least UV).
About notation - I think it is helpful to list UV settings in the full format I use (rather than just how many volts down) for two reasons:
1 – The reference voltages vary depending on kernel. So it could be misleading to report what the reduction in voltage is without reporting the reference. At 1200Mhz, Zen’s Infusion A/B uses 1275millivolts while Entropy’s DD uses 1300millivolts (voltages match at other frequencies). I’m not sure what the voltages are in stock kernel.
2 – Listing the final voltages allows you to see how much jump in voltage there is from one frequency to the next (large jump could possibly increase instability)... this aspect is not as obvious if we just list how many volts below the reference.
Setting set 0
100 Mhz: 950mv max – 100mv = 850 millivolts
200 Mhz: 950mv max – 100mv= 850 millivolts
400 Mhz: 1050mv max – 100mv = 950 millivolts
800 Mhz: 1200mv max – 100mv = 1100 millivolts
1200 Mhz: 1275mv max – 100mv = 1175 millivolts
1600 Mhz: 1400mv max – 50mv = 1350 millivolts
Duration: Tested less than one day.
Results: Reported in original thread: caused unwanted reboot while surfing. After that the battery indicator jumped.
Setting set A.
100 Mhz: 950mv max – 75mv = 875 millivolts
200 Mhz: 950mv max – 50= 900 millivolts
400 Mhz: 1050mv max – 75mv = 975 millivolts
800 Mhz: 1200mv max – 100 mv = 1100 millivolts
1200 Mhz: 1275mv max – 75mv = 1200 millivolts
1600 Mhz: 1400mv max – 100mv = 1300 millivolts
Duration: Tested 3 days heavy use
Results:
* “Rainbow Screen After Trap Game” – I tried the game “Trap” which was recommended in a thread somewhere as being a good test to find stability problems using UV. Sure enough upon exiting the game once, my screen turned to rainbow colors. I rebooted to restore screen to normal (same UV). I played the game for 15 minutes exiting a few more times, no more problems.
* “Widgets Lost” - Once after reboot I lost all my widgets (Tasker, Color Notes, Elixir). They did not come back even when I went to stock voltages and rebooted. Had to manually restore each of my widgets.
* “Discolor Upon Screen On” - Once in awhile when turning on screen, some colors are initially wrong (mostly I notice the white labels of my icons are yellow or pink). It goes away very quickly - either after I touch the screen or after scroll around a little. After that everything is normal.
* “Flash Upon Screen On” - Once in awhile when turning on the screen, I see a white flash for a fraction of a second (sort of like with an old TV tube when you turn it on or off). After that everything is normal.
These last two symptoms (“Discolor Upon Screen On” and “Flash Upon Screen On”) occurred probably once per day over the course of the three days relatively heavy usage.
Setting set B
100 Mhz: 950mv max – 25mv = 925 millivolts
200 Mhz: 950mv max – 25= 925 millivolts
400 Mhz: 1050mv max – 25mv = 1025 millivolts
800 Mhz: 1200mv max – 75 mv = 1125 millivolts
1200 Mhz: 1275mv max – 50mv = 1225 millivolts
1600 Mhz: 1400mv max – 75mv = 1325 millivolts
Duration tested: 3 days heavy use
Results:
* “Discolor Upon Screen On” – Same as above. 2 or 3 times over three days heavy use
* “Flash Upon Screen On” – Same as above. Once over three days.
setting set C
100 Mhz: 950mv max – 15mv = 935 millivolts
200 Mhz: 950mv max – 15= 935 millivolts
400 Mhz: 1050mv max – 15mv = 1035 millivolts
800 Mhz: 1200mv max – 50 mv = 1150 millivolts
1200 Mhz: 1275mv max – 25mv = 1250 millivolts
1600 Mhz: 1400mv max – 50mv = 1350 millivolts
Duration Tested: 3 days heavy use
Results:
* “Discolor Upon Screen On” – Same as above. 2 or 3 times
(Did not have the Flash upon screen on)
setting set D = 0 undervolt – use Zen’s default settings.
Duration: about 2 weeks experience with GB in this configuration
“Discolor Upon Screen On” – Never saw it
* “Flash upon screen on” – Never saw it, but did see a similar flash just once in my phone application when I removed phone from ear to look at keypad.
** EDITED TO ADD - Today after posting this, I noticed the flash upon screen on" while using no UV, 100-1200Mhz. Maybe I just wasn't looking for it before.
Other Testing Using Specific Applications:
I did a lot of testing with these programs on settings A, B, C and saw no anomalies. For settings A, B, and C, did the following:
SetCPU “Stress Test” for approximately one minute
“Stability Test” Applicaiton– “Scaling Stability Test” subtest for approx 20 minutes (battery gets up to about 115F).
“Stability Test” Applicaiton – “CPU+GPU Stability Test” subtest for approx 10 minutes (actually did this only in B, C, didn't try it in A)
I played the game "Trap" (that caused the problem in setting A) for 15-20 minutes in B, C, exiting and reentering a few times. Didn't see any problems.
Interestingly, when I run Quadrant it sometimes flakes out (returns to Quadrant start screen without any result) and somtimes run to conclusion. But this happens even on stock voltages, and I think I remember it's a problem with Quadrant that others have seen, so I’m inclined to think it is not an indicaion of instability I should worry about.
Analysis:
It looks like B is the most UV I can apply without significant problems appearing during 3-day test. But I still had some minor anomalies I notice occasionally when turning screen on (brief flash and brief discoloration),.but they occur to certain extent even at less UV (C) and at zero UV (D)
All of the above real-life testing in A, B, C was done with max frequency of 1200 (because I wanted to rule out 1600 as a problem).
I used 1600 only during the specific stability test appliations.. that ran fine and also in the D configuration that ran fine. So the problems (if they are problems) come from UV, not from using 1600Mhz.
Questions:
Do you think discoloration upon turning on the screen or flash upon turning on is cause for concern? The symptom itself is not an inconvenience but I’m wondering if it’s warning me about something else going on...(***)
I don’t really have a feel for what change in battery life occurs with these different settings. Seems very difficult to quantify. Any thoughts?
By the way, I'm using ULCB3 stock rooted GB. Using Zen's Infusion-A kernel. cpu control using setcpu: Mostly 100-1200Mhz cpu frequency, conservative cpu governor with the Up/Down threshholds tweaked to 95/45, noop io scheduler.
I installed this configuration about a month ago using qkster's Heimdall one-click.Never had any problems other than those mentioned above which may or may not be problems.
*** I have to confess, I wiped Davlick cache and wiped the other cache at that time, but never did the "factory data wipe" because I had data on my phone that wasn't backed up. I'm not sure if those particular instructions required factory data wipe or not but I remember it was mentioned as good practice. It occurs to me maybe these subtle brief strange symptoms upon turning on the screen are remnants from incomplete wipe?

I went back to stock and still had the occasional occurence of discolored screen upon waking from deep sleep.
It seems harmless, goes away if cycle the screen.
So I re-established UV. I have had my phone at the following settings since 9/17/12. No problems for me other than that occasional discoloration or flashing upon waking for sleep and one other problem where the phone would occasionally ring and I could see the call but not hear the caller (they could hear me). I eventually traced that to tweaking my governor settings... will post that in another thread.
100 Mhz: 950mv max – 50mv = 900 millivolts
200 Mhz: 950mv max – 25= 925 millivolts
400 Mhz: 1050mv max – 50mv = 1000 millivolts
800 Mhz: 1200mv max – 75 mv = 1125 millivolts
1200 Mhz: 1275mv max – 50mv = 1225 millivolts
1600 Mhz: 1400mv max – 75mv = 1325 millivolts

electricpete1 said:
I went back to stock and still had the occasional occurence of discolored screen upon waking from deep sleep.
It seems harmless, goes away if cycle the screen.
So I re-established UV. I have had my phone at the following settings since 9/17/12. No problems for me:
100 Mhz: 950mv max – 50mv = 900 millivolts
200 Mhz: 950mv max – 25= 925 millivolts
400 Mhz: 1050mv max – 50mv = 1000 millivolts
800 Mhz: 1200mv max – 75 mv = 1125 millivolts
1200 Mhz: 1275mv max – 50mv = 1225 millivolts
1600 Mhz: 1400mv max – 75mv = 1325 millivolts
Click to expand...
Click to collapse
1. discolored screen: zen told me about these. I've not seen it..no known harm effects though.
2. I've pushed the 1600 to -125mV; 1200 to -100mV without issues.

[OPTIMIZATION][UNDERVOLTING] Testing different voltages and CPU behavior

I've asked the mods to close my other thread.
What I'll do in this thread is to test kernels and see which will be the best and or the most reliable undervolting parameters.
I know that each CPU/GPU are different, it will be only a reference for what can be done. I'll run extensive tests, stress test and real life test on the Nexus 7 device 32GB.
I'll reserve a couple of post areas because i want it to be a permanant thread and i put my device at risk for you my firends anyway it is not really an issue lol
I'll do the testing like that : ( how i'll do it and conditions )
1. I'll write the kernel name and version i am using for the test
2. I'll post the screenshots of the settings and/or a raw text of the settings for the specific kernel.
3. Trickstermod will be used for tweaking
4. Quadrant test for people who live for it
The conditions for the undervolt pass the test are the following
1. Running glowball for 30 minutes without crashing
2. Running Stability test 2.5 for 30 minutes. ( RUNNING EACH OF THE TESTS FOR 30 MINUTES C-A-D CLASSIC/CPU+GPU/SCALING TEST ) all in userspace mode.
Those settings will be the lower voltage achievable for me. You can use it as a reference but I cannot guarantee it will work for your device.. What I can suggest is using the boot delay option from the trickstermod menu. If we see that some settings are reliable for a lot of people, it would be nice to have help from some coders to write an init.d script with those settings. or just sharing other experiences. This is not a thread where I have the ultimate knowledge, but a thread who everybody can share their experiences, settings and so on to achieve the ultimate goal of performance and very low power consuption and battery life.
Those test will be time consuming but it is ok.
I do not expect any form of donation for that
If it helped you a little bit, you can just hit the help button and it will be my payday =)
Thank you very much
PS : For people giving 1 Star to the thread before I ever post the first undervolting settings, well, I do not know what to say. For the others who already tried the differents settings I,ll post day to day, feel free to post comments and rate the thread. You can even rate it 1 star if you want because you tried it. But for people who gave negatives reviews even if i didn't post any settings, please get a life.

December 4th 2012 6:06PM 1st stable aggressive undervolting
December 4th 2012, 6:06PM
ROM: Scott's CleanRom 3.0
Kernel : 3.1.10-franco.Kernel [email protected] #30
Stability issues : No
CPU frequencies settings : [email protected] Mhz
Governor : On Demand
I/O scheduler : Deadline
Read Ahead buffer : 2048
GPU Max frequency : 526
CPUQuiet Power Management : balanced
VOLTAGE SETTINGS : MPU
1300 Mhz @ 975 mv
1200 Mhz @ 950 mv
1100 Mhz @ 925 mv
1000 Mhz @ 900 mv
900 Mhz @ 875 mv
800 Mhz @ 850 mv
700 Mhz @ 825 mv
600 Mhz @ 800 mv
500 Mhz @ 775 mv
400 Mhz @ 750 mv
300 Mhz @ 725 mv
200 Mhz @ 700 mv
100 Mhz @ 675 mv
Notes for this undervolting
CPU stable at 975 mv for 1300 Mhz. Tried 970 mv with -5 incremental for other frequencies but the device just crashed. reverted back +5mv for all frequencies and run a second test and it was 100% stable.
The stock CPU voltage settings is 1175mv for 1300 Mhz and so on by 5mv incremental. We are able to achieve performance and stability with a global undervoltage of 200 mv. Actually this is a lot. What happened with the battery life ? Almost 8 hours gain vs the stock settings. This is a lot considering there is no drop with performances.
Edit : Just made other extensive testing. Played deadzone, dead trigger and gta 3 without any glitches. They run smoothly without freezes. We could assume this config is quite stable.
Next step would be undervolting bus and memory while trying keeping those voltages for the cpu. Ill need help to achieve that because i am not a big coder.

Ongoing testing ( may not be stable ) Dec 5 2012
ROM: Scott's CleanRom 3.0
Kernel : 3.1.10-franco.Kernel [email protected] #30
VOLTAGE SETTINGS : MPU
1300 Mhz @ 975 mv
1200 Mhz @ 950 mv
1100 Mhz @ 925 mv
1000 Mhz @ 900 mv
900 Mhz @ 875 mv
800 Mhz @ 850 mv
700 Mhz @ 825 mv
600 Mhz @ 800 mv
500 Mhz @ 775 mv
400 Mhz @ 710 mv
300 Mhz @ 640 mv
200 Mhz @ 635 mv
100 Mhz @ 625 mv
With on-demand, the tablet crash.
With interactive and other governors other than on-demand, seems working fine. Needs more testing

Reserved 3
Reserved 3
http://forum.xda-developers.com/showthread.php?t=2009702
He uses my voltage settings as his new kernel base I think. I must verify with him.
Sparksco use 1600 mhz with a ultra low voltage of 1100 mV.
Expect great battery life with his Rom and kernel

Reserved 4
Reserved 4

Reserved 5
Reserved 5

Good job, keep it up Mr. jsmasterx :good:

jsmasterx said:
December 4th 2012, 6:06PM
ROM: Scott's CleanRom 3.0
Kernel : 3.1.10-franco.Kernel [email protected] #30
Stability issues : No
CPU frequencies settings : [email protected] Mhz
Governor : On Demand
I/O scheduler : Deadline
Read Ahead buffer : 2048
GPU Max frequency : 526
CPUQuiet Power Management : balanced
VOLTAGE SETTINGS : MPU
1300 Mhz @ 975 mv
1200 Mhz @ 950 mv
1100 Mhz @ 925 mv
1000 Mhz @ 900 mv
900 Mhz @ 875 mv
800 Mhz @ 850 mv
700 Mhz @ 825 mv
600 Mhz @ 800 mv
500 Mhz @ 775 mv
400 Mhz @ 750 mv
300 Mhz @ 725 mv
200 Mhz @ 700 mv
100 Mhz @ 675 mv
Notes for this undervolting
CPU stable at 975 mv for 1300 Mhz. Tried 970 mv with -5 incremental for other frequencies but the device just crashed. reverted back +5mv for all frequencies and run a second test and it was 100% stable.
The stock CPU voltage settings is 1175mv for 1300 Mhz and so on by 5mv incremental. We are able to achieve performance and stability with a global undervoltage of 200 mv. Actually this is a lot. What happened with the battery life ? Almost 8 hours gain vs the stock settings. This is a lot considering there is no drop with performances.
Edit : Just made other extensive testing. Played deadzone, dead trigger and gta 3 without any glitches. They run smoothly without freezes. We could assume this config is quite stable.
Next step would be undervolting bus and memory while trying keeping those voltages for the cpu. Ill need help to achieve that because i am not a big coder.
Click to expand...
Click to collapse
how is the performance is it good because i have a lot of lag when i pull down the notification bar

sharjackmission said:
how is the performance is it good because i have a lot of lag when i pull down the notification bar
Click to expand...
Click to collapse
Undervolting should not impact the performance of the CPU.
What you can do is taking a look at the numbers and raise voltage a little. But it might be a lot of reasons why it is laggy. Possibly the governor ?
Other people tried the same settings without issues. But raisong the voltage a little wont drain the battery a lot as the number I gave are agressively low.
Cheers

Running on these settings and everything running smoothly. Thanks for the thread.
Sent from my Nexus 7 using Tapatalk 2

Running stock 4.2.1 with MKernel A19 & TRINITY... These voltages seem to be alright.
I am also using interactive and the deadline scheduler.
All is smooth so far... I'll report back if I run into any trouble.
UPDATE - Had to revert. Started getting freezes and crashes.
Trinity kernel's stock voltages seem to play nicely... Anything less is glitchy.

monsieurtalbot said:
Running stock 4.2.1 with MKernel A19 & TRINITY... These voltages seem to be alright.
I am also using interactive and the deadline scheduler.
All is smooth so far... I'll report back if I run into any trouble.
UPDATE - Had to revert. Started getting freezes and crashes.
Trinity kernel's stock voltages seem to play nicely... Anything less is glitchy.
Click to expand...
Click to collapse
For underclocking aaggressively for now I only recommand Franco Kernel. All other kernels Causes stability problems with the same voltages.
Ill let you know soon with that developpement.

Can't wait for m kernel optimizations

krazeecracker said:
Can't wait for m kernel optimizations
Click to expand...
Click to collapse
As soon as they realease the next version I'll test it.
For now the only thing it does is freezing the tablet.
The best undervolting I was able to achieve for now was with Franco Kernel because of the way the kernel is setting up. M-kernel and other boost Bus and memory speed that causes crashes with agressive undervolting.
Doing so, the performance gain is minimal and the battery life truly suffer at the end.
You can get except a few more FPS in certain games but not really noticeable.

jsmasterx said:
As soon as they realease the next version I'll test it.
For now the only thing it does is freezing the tablet.
The best undervolting I was able to achieve for now was with Franco Kernel because of the way the kernel is setting up. M-kernel and other boost Bus and memory speed that causes crashes with agressive undervolting.
Doing so, the performance gain is minimal and the battery life truly suffer at the end.
You can get except a few more FPS in certain games but not really noticeable.
Click to expand...
Click to collapse
No rush man, your work is amazing.

jsmasterx said:
As soon as they realease the next version I'll test it.
For now the only thing it does is freezing the tablet.
The best undervolting I was able to achieve for now was with Franco Kernel because of the way the kernel is setting up. M-kernel and other boost Bus and memory speed that causes crashes with agressive undervolting.
Doing so, the performance gain is minimal and the battery life truly suffer at the end.
You can get except a few more FPS in certain games but not really noticeable.
Click to expand...
Click to collapse
100% of everything you said in that post is untrue. Please make sure the information you pull out of thin air is correct before stating them as fact.
Also voltage tolerance at a certain frequency is device dependent. Not kernel dependent. No amount of circumstantial evidence will change the laws of physics.
One more thing, your frequency table in the first post is wrong. The A9 G core DVFS table does not go below 480MHz. Franco's table is wrong and as a result so is yours.

This thread looks interesting. If you'd like you can test my kernel attached to THIS post as a flashable zip.
:beer:

sparksco said:
This thread looks interesting. If you'd like you can test my kernel attached to THIS post as a flashable zip.
:beer:
Click to expand...
Click to collapse
I will. What would you like me to do after ?
Sent from my Nexus 7 using xda app-developers app

Metallice said:
100% of everything you said in that post is untrue. Please make sure the information you pull out of thin air is correct before stating them as fact.
Also voltage tolerance at a certain frequency is device dependent. Not kernel dependent. No amount of circumstantial evidence will change the laws of physics.
One more thing, your frequency table in the first post is wrong. The A9 G core DVFS table does not go below 480MHz. Franco's table is wrong and as a result so is yours.
Click to expand...
Click to collapse
I did not attack your kernel whats so ever i dont know why you are taking it personal.
As far as i know franco`s table is accurate and the G core can go under 480 mhz. To make sure i what i advance is true i even pluged the N7 to a debug box. My friend who is an analyst programmer certified it also
Sent from my Nexus 7 using xda app-developers app

jsmasterx said:
I will. What would you like me to do after ?
Sent from my Nexus 7 using xda app-developers app
Click to expand...
Click to collapse
Whatever the goal of this thread is I suppose. It's based on bricked kernel but I modified it a lot so it's not really much like it anymore. To some it up it overclocks to 1.6ghz and has quite a few governors. I'm testing smartassv2 right now but I have a feeling it's not good for battery. I haven't really tested many of the other governors but I've never had any of them lock up on me. Voltage control is also supported. No GPU overclocking though.
Sent from my Nexus 7 using Tapatalk 2

[Q] Best undervolt values for this tablet?

I have recently installed PimpMyROM for my tablet and have found this nice voltage setting feature.
Anyone have any good voltage values for longer lasting battery life without any cases of random reboots?

Best guaranteed to work is really not dialed into your specific tab and user habits.
Setcpu is an excellent app that can help you out with testing. It has a stress test future to make it easy to see if your Undervolt settings are stable.
Google Play claimed it isn't compatible for my tab so I grabbed it off Xda. It works fine. I gotta donate still... (and so should you if you get it here)
Btw: Setcpu has Undervolt settings built in too. You may want to freeze PMR while testing to be sure their settings are not conflicting.
Sent from my SGH-I997 using Xparent Red Tapatalk 2

But as for a starting place...
I have both my daughter's p6210 running smooth with these settings:
1200 MHz 1175 mV
1000 MHz 1050 mV
800 MHz 950 mV
500 MHz 925 mV
200 MHz 900 mV
The most intensive thing they do is play Survival Craft (for hours). Tabs were getting excessively hot before I Undervolted them. No crashes in days...
They're both on CM10.1
Sent from my SGH-I997 using Xparent Red Tapatalk 2

My voltages:
1400 MHz 1325mV
1200 MHz 1225mV
1000MHz 1175mV
800MHz 1150mV
500MHz 1050mV
200MHz 975mV
Its not much battery saver but rom is stable

[Q] Best undervolting settings for custom kernel

If you use a custom kernel like Aero Kernel, what is your best undervolting settings?
I have been using this for a week and my phone is very stable
300 mhz - 990 mV
384 mhz - 990 mV
600 mhz - 1000 mV
787 mhz - 1000 mV
998 mhz - 1025 mV
1094 mhz - 1025 mV
1190 mhz - 1050 mV
Any suggestions to undervolt it even better?