Develop Bugs

Undervolting

I wanted to know some more about undervolting and was hoping someone could help and explain a bit. Basically, what I'm seeing is when I undervolt my device on the max side of things, eventually the device freezes and needs a battery pull or reboots. When I don't touch the max voltage values and only drop the min values the phone seems more stable and doesn't reboot. Can someone explain if my thinking of only undervolting the min values is correct and why this may be happening. Also, what would be the proper way to undervolt the phone? I have been using system tuner to do so on deck's 1.3 ROM using the Lee +sbc kernel. Thanks for taking the time to read this and for all the helpful responses.
Sent from my Decked Evo running Lee+sbc... It's easier this way.

I have this same question! I was trying to figure this out becuase the freedom kernels have something to do with under and over voltage to allow better OC? not sure on why the you would need and over voltage to over clock?...

What is your ROM/Kernel setup?
Remember that undervolting and underclocking are two different things. Over/underclocking, via apps like setcpu, raise/lower the frequency at which your processor operates. Over/undervolting raises/lowers the power voltage available to your processor at any given frequency. This can potentially cause problems if you have a kernel set to undervolt your processor while running an app like setcpu to overclock it. This may be why you are seeing issues with your phone.

pmacevad said:
[snip]
I have been using system tuner to do so on deck's 1.3 ROM using the Lee +sbc kernel.
[snip]
Sent from my Decked Evo running Lee+sbc... It's easier this way.
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Concordium said:
What is your ROM/Kernel setup?
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Click to collapse
OP clearly states he's running Deck's 1.3 and Tiamat 3.3.7 (aka LEE kernel)
OP should also state Deck's ROM version but I'm assuming 1.3d as it's most popular next to 1.3 Stable.
I'm running the same setup - Deck's 1.3d with LEE SBC. I'd like someone to explain (as the OP also asked) the difference between the MIN and MAX sides of the undervolting equation please.
(I do understand underclocking AND that it is a separate and different animal and for the record, my EVO is UC'd to 128/499MHz and using Smartass governor)
I'm just not sure what I'm looking at in the ST interface (what's the first number and what's the number in [] brackets?) and also not sure just why there is both a min and max voltage for each frequency and how it affects performance.
Thanks much for any inputs.
J.

I use vipermod and terminal emulator for aosp roms its much more stable than using system tuner and you can drop all voltages with a single command it all depends on your particular hardware but typically around -100 the phone will lag or freeze i usually stick to -50 at stock voltages and -25 on overclock i never overclock over 1075mhz as anything higher and my phone tries to cook my fingers however now im oc to 1.6ghz on my et4g with a 200mhz min and it stays nice and cool like it was clocked at 1.2ghz stock the exynos is capable of clock speeds up to 2 ghz but the phone doesnt handle those speeds well similar to the evo not liking anything over 1.19 at 1.2 on the evo theres a good chance of frying the logic board or bursting the battery from heat if you overclock dont undervolt too much as it makes the processor get really really hot due to it having to work harder from lack of energy to power it
We are legion, for we are many
Sent from my Anonymous DeathStar in the depths of GalaXy S2

To answer the min/max at each freq min is the lowest voltage that freq will run while idle max is the highest voltage the freq will run while in use the voltages are depenedant on the load running at the particular freq ie how many process' are running the more process' the higher the voltage required to power the processor
We are legion, for we are many
Sent from my Anonymous DeathStar in the depths of GalaXy S2

Is there an app the will show actual voltage the CPU is using in real time?
Sent from my Synergized Aggressive Lionfish Evo using the XDA app

bmw pro will u can set the mv on the widget or set recording in the app and it will log the info
We are legion, for we are many
Sent from my Anonymous DeathStar in the depths of GalaXy S2

I had a similar issue with undervolting and underclocking. I was setting my CPU min/max to 128-499 MHz and undervolting to -75 or -100 using Lee with Smartass v1. But I was getting too many random reboots and freezes on each ASOP rom I tried (e.g. Deck 1.3d, CM7).
I've been playing around with these settings. I changed my CPU to 128-576, no undervolting, and SZ 2.2.1 with SavagedZen governor. I haven't had any random reboots and my batter life is about the same...plus my phone is MUCH snappier. I'm still getting a little screen on lag but not nearly as much as I was at 128-499 and undervolted.
As a note, I normally run Deck 1.3d as my daily driver but for the last couple days I've been running KWIQ. It's definitely giving 1.3d a run for its money as becoming my daily driver.
Anywho, are there any rules of thumb with undervolting and underclocking? Like is 128 MHz is too low with -100 undervolting? Or are these things pretty much phone dependent? I know each phone seems to respond different to these things.

-EViL-KoNCEPTz- said:
To answer the min/max at each freq min is the lowest voltage that freq will run while idle max is the highest voltage the freq will run while in use the voltages are depenedant on the load running at the particular freq ie how many process' are running the more process' the higher the voltage required to power the processor
Click to expand...
Click to collapse
Thank you. That made good sense to me. Question then: is it suggested/typical to drop min and max by equal amounts or is it typical to drop min more (so there's juice for the proc under load but maybe being more aggressive with the sleeping/idle side of things or can the proc run at a given frequency at different voltages)?
jackfrost909 said:
I'm just not sure what I'm looking at in the ST interface (what's the first number and what's the number in [] brackets?)
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Are you familiar enough with ST to shed some light on this? Please if so. Thank you.
detcup4evr said:
Is there an app the will show actual voltage the CPU is using in real time?
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Click to collapse
-EViL-KoNCEPTz- said:
bmw pro will u can set the mv on the widget or set recording in the app and it will log the info
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Click to collapse
Though I have to recheck this I don't remember BMW showing the voltage being used at each frequency just the overall voltage draw. If you know otherwise or another tool that does, please share
Thanks for all the help.
J.
--
Tapa Tapa Tapa..
Let's see.. My phone flies, my battery doesn't suck.. and your point was.... ?
OG EVO - Deck'd and LEE'd because it's just better this way.

Lionfish kernel
Has anyone tried undervolting with lionfish kernel on SENSE Roms, is it stable?

einstein562 said:
Has anyone tried undervolting with lionfish kernel on SENSE Roms, is it stable?
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I use aggressive and it works well but some phones don't like it, hopefully I can get vipermod to work, and that will allow you to adjust each frequency independently
Sent from my Synergized Aggressive Lionfish Evo using the XDA app

I actually just got rid of lionfish aggressive on MikG3.11
I had a lot of lagginess, but battery life was really good... Back to anthrax for me, lionfish was based at one point on freedom kernels I thought, maybe one of those would be better...?
What's the best thing to use to control undervolting on sense roms?
Sent from my PC36100 using Tapatalk 2

Is the battery life improvement substantial when undervolting?
I have governators set at 240-650max and am getting decent life on my ics savoca kernel.
What % improvements are obtained?

Well I don't have logcats and scientific evidence, but I saw about 12 hour days, with moderate use, everything syncing, lots of text a few calls, hotspot for an hour or so, some web browsing, but the random revolts and lagginess on that was horrible, freedom was better.... It's worth it to underclock
I have everything set to 384-1152.
Different governors for profiles, screen off @ conservative because I have a lot to sync
Sent from my PC36100 using Tapatalk 2

Best Overclock settings specifically for the Play?

I'm using NoFrills CPU and want to find the right balance between overclocking, performance and battery...
What speeds and governors are everybody using for their Plays?

I'm using 1.2 Ghz max 130 Mhz min with SmartassV2 and sio. All seems okay to me.

I'm using 921mhz-122mhz intellidemand2 with sio governor and everything is smooth + battery is great
Sent from my R800i using xda premium

1401Mhz Max, 180Mhz Min (when Screen On), 785Mhz Max-180Mhz Min (When Screen Off)
Noop + InteractiveX
---------- Post added at 12:27 PM ---------- Previous post was at 12:26 PM ----------
1401Mhz Max, 180Mhz Min (when Screen On), 785Mhz Max-180Mhz Min (When Screen Off)
Noop + InteractiveX

So many different settings!
Was hoping there'd be a 'common' setting that everyone kind of determined was best.
Thank though.
Still interesting, and would like to see what more people are using still.

Mines currently 1.613 Ghz Max, 245 Mhz Min. Virtuous Governor, Noop I/O Scheduler.
On intensive apps I change the max clock to 1.901Ghz however this I don't recommend for most people.
I also only use 1.9Ghz when using Android 2.3.7 with DoomKernel, as only that Kernel seems to allow for voltage changes... Which i apply when using that kind of speed, whereas the default voltages are much higher for that clock than I usually set.
Everyone's Play is different, and not all Plays can sustain high clocks at specific voltages. You need to find your own 'sweet spot'.

Spizzy01 said:
You need to find your own 'sweet spot'.
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Is there an app for that?

No.
You need to increase your clock little by little until you're happy. Then, if you're on GB using DoomKernel you need to lower the voltage as much as you can without it crashing if you want it perfect.
Most people simply oc though and don't bother with the voltages, but it will reduce power consumption and extend the life of your phone with the OC enabled.. As normally running your CPU past its specification will wear it out faster.
Sent from my R800i using xda premium

As DiKeJ said in his ROM thread:
In my opinion, interactiveX, and frequency of CPU 364.8-1305.6MHz gives awesome stability and performance
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:good:

TRUE FACT.

you should use a kernel that allows you to undervolt... there was some article with the galaxy S3, where they tested different settings with OC+UV and YES, Under Volting gives better battery life!!
A lot of people here say, that UV will have no effect on battery, but they have no idea how a processor works... so they just should stfu!!

Duel Core cpu

I'm just wondering if i'm not used to seeing dual core cpu frequencies. Is it normal to see your minimum frequency jump around between 384mhz and 1026mhz regardless of where you place the sliders?

Perfectly normal. Do you know which CPU governor you're running? Some governors limit the CPU's ability to make large jumps like that, but others allow it.

borxnx said:
Perfectly normal. Do you know which CPU governor you're running? Some governors limit the CPU's ability to make large jumps like that, but others allow it.
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I'm running the Anthrax kernel on "Interactive".

MikeWjF said:
I'm running the Anthrax kernel on "Interactive".
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Rethinking through your original post, did you mean that the CPU speed was jumping outside of the min/max parameters?
I'm not familiar with the Anthrax kernel, but Interactive is one of the "jumpier" governors.

borxnx said:
Rethinking through your original post, did you mean that the CPU speed was jumping outside of the min/max parameters?
I'm not familiar with the Anthrax kernel, but Interactive is one of the "jumpier" governors.
Click to expand...
Click to collapse
No, they're staying within the max and min frequencies.
Sent from my SPH-L710 using Tapatalk 2

Undervolting wonder

Can anybody post the maximum undervolting settings for galaxy w?
Currently i have all settings -100mv. How much further can i go? How can i identify if I've overdone it?
Current Kernel: [Kernel][ICS] Arco+ V1.3's kernel & HurtSkyV2's kernel 29/3/2013

1.4 Ghz run stable down to 1.075 V for me.
With 1.050 V, is freezes after some seconds of the AnTuTu stability test.
I guess that stock voltage for 1.4 Ghz is 1.250 V, as it can be seen in arcos repo.

Nice under voltage

Yes, i am satisfied with the result.
Guess that 1.4 Ghz might be some kind of sweet spot, as my lowest voltage with 1.0 Ghz is something about 0.925 V.
Depends on the scenario, but the energy-per-cpu-cycle-ratio might be better with 1.4 Ghz after all, plus full calculation-thrust
Also had it running at 1.8 Ghz, and at one point with 2 Ghz, but i do not remmeber the voltages exactly.
Might have been something around 1.275 V for thw 1.8 Ghz one, also a good result.
By the way, there are quite big differences:
My Intel Core 2 Duo T6500 runs at its full 2.1 Ghz with the lowest possible voltage, 0.9250V, normal is 1.150V
On the other side, i had a desktop E6600, which needed much additional voltage for little OC, and was also bad for UV.
(seems as it was an exception, as they were known for excellent oc capabilities).
Sorry for OT

XR-7 said:
Yes, i am satisfied with the result.
Guess that 1.4 Ghz might be some kind of sweet spot, as my lowest voltage with 1.0 Ghz is something about 0.925 V.
Depends on the scenario, but the energy-per-cpu-cycle-ratio might be better with 1.4 Ghz after all, plus full calculation-thrust
Also had it running at 1.8 Ghz, and at one point with 2 Ghz, but i do not remmeber the voltages exactly.
Might have been something around 1.275 V for thw 1.8 Ghz one, also a good result.
By the way, there are quite big differences:
My Intel Core 2 Duo T6500 runs at its full 2.1 Ghz with the lowest possible voltage, 0.9250V, normal is 1.150V
On the other side, i had a desktop E6600, which needed much additional voltage for little OC, and was also bad for UV.
(seems as it was an exception, as they were known for excellent oc capabilities).
Sorry for OT
Click to expand...
Click to collapse
Thanked for sharing your numbers with everyone =)! may i know how can i safely experiment with undervolting? like what do i do to make sure there will be no hard-breaking or equivalent events from happening? and also how do i know i should stop and choose the voltage 1 level higher than my current value (i.e. when is the value too extreme that it could be bad for my phone)? Thank you in advance!

I shared my voltage in hadidjapri's CM9 kernel thread. Let me dig up the link for you...
Edit: Aha! Found it:
http://forum.xda-developers.com/showthread.php?p=38516105
As you can see in the table I've posted there, the undervolting varies according to frequency. I've undervolted by 175 on 1 GHz, and perhaps can still go 25 lower.
Sent from my GT-I8150 using xda app-developers app
---------- Post added at 03:00 AM ---------- Previous post was at 02:50 AM ----------
egagah said:
Thanked for sharing your numbers with everyone =)! may i know how can i safely experiment with undervolting? like what do i do to make sure there will be no hard-breaking or equivalent events from happening? and also how do i know i should stop and choose the voltage 1 level higher than my current value (i.e. when is the value too extreme that it could be bad for my phone)? Thank you in advance!
Click to expand...
Click to collapse
My suggestion is to use the numbers in the table I've posted. Use the phone for 2-3 days and see if it becomes wonky (random reboots, hangs, etc). Then try reducing the voltages to the "extreme undervolt" values in the graph I attached to that posting. Then lower the voltage for the 'sleep' frequencies first (369 and less), and slowly work your way to your maxfreq.
Sent from my GT-I8150 using xda app-developers app

For me it´s a bit different. At the upper frequencies (1000-1400MHz) I´m at the extreme UV voltages. But for the lower frequencies I need to be +25mV above the extreme UV settings.
So there is noone who can tell what the sweet spots for all the frequencies are. Each CPU is different and everyone has to find out his sweet spots himself.
For stability tests there are even some apps at the play store, though I found the facebook app to be the best stability test app at all. Where all the stability tests passed the facebook app crashed if I undervolted a little bit to much.

pepoluan said:
I shared my voltage in hadidjapri's CM9 kernel thread. Let me dig up the link for you...
Edit: Aha! Found it:
http://forum.xda-developers.com/showthread.php?p=38516105
As you can see in the table I've posted there, the undervolting varies according to frequency. I've undervolted by 175 on 1 GHz, and perhaps can still go 25 lower.
Sent from my GT-I8150 using xda app-developers app
---------- Post added at 03:00 AM ---------- Previous post was at 02:50 AM ----------
My suggestion is to use the numbers in the table I've posted. Use the phone for 2-3 days and see if it becomes wonky (random reboots, hangs, etc). Then try reducing the voltages to the "extreme undervolt" values in the graph I attached to that posting. Then lower the voltage for the 'sleep' frequencies first (369 and less), and slowly work your way to your maxfreq.
Sent from my GT-I8150 using xda app-developers app
Click to expand...
Click to collapse
alright i'm trying with the extreme UV settings now (with +25mV for freq <1000mhz, will reduce later if stable) but i'm not sure if its the new Queen Anne's Revenge v2.3 rom, hurtsky's 2.1 kernel, or the usage of smartassH3 + sio that is causing my phone to feel less responsive (like takes 2-3x longer time to launch apps like whatsapp, boat browser, also launching incredicontrol twice in a row crashes incredicontrol lol). Is this a sign that I am undervolting too much? because I've tried raising all values by up to 50 from the extreme UV but doesn't really help. also tried changing smartassH3 to smartassv2 (my previous governor)

egagah said:
alright i'm trying with the extreme UV settings now (with +25mV for freq <1000mhz, will reduce later if stable) but i'm not sure if its the new Queen Anne's Revenge v2.3 rom, hurtsky's 2.1 kernel, or the usage of smartassH3 + sio that is causing my phone to feel less responsive (like takes 2-3x longer time to launch apps like whatsapp, boat browser, also launching incredicontrol twice in a row crashes incredicontrol lol). Is this a sign that I am undervolting too much? because I've tried raising all values by up to 50 from the extreme UV but doesn't really help. also tried changing smartassH3 to smartassv2 (my previous governor)
Click to expand...
Click to collapse
Undervolting doesn't affect performance, at least not directly.
What it affects are power consumption (i.e., battery life) and stability; some components within don't perform reliably with too low a voltage, and may internally reset themselves. This causes the kernel to go into panic (because the state in the kernel no longer matches the state of the hardware), and as a result, crashes.
Sent from my GT-I8150 using xda app-developers app

ok. i used CWM to clear cache and dalvik cache, which forced the rom to "upgrade" again. The lag is significantly less noticable =)! Perhaps when upgrading rom (non-pristine), it is better to clear cahces

how sorry i'm a newbie here may i ask how to undervolt (or a link)? i've been having problem with battery life so perhaps this will prolong it further..

Download incredicontrol and u can use that app to set voltages. Follow graph given by pepo . Make sure u do not set as boot first. Test for like a day and if no phone hanging or restart then u can set as boot

Freq-voltage(mV)
122-775
245-775
368-850
768-900
806-950
1 02-975
1,11-1000
1,2-1025
1,3-1050
1,4-1100
1,5-1150
1,6-1200
1,7-1250
1,8-1325
I use these for my daily use, and it seems no problem at all.
Sent from my GT-I8150 using xda premium

Deleted

Did anyone experience random Shutdowns or reboots after undervolting?

vklexer said:
Did anyone experience random Shutdowns or reboots after undervolting?
Click to expand...
Click to collapse
Nope
Sent from my GT-I8150 using xda premium

ElementalX kernel - what's the fuss about

Hey guys
Before rooting my tablet I want to know something. Whats the fuss about this specific kernel? I literally see it everywhere ( well done to the dev )
I kinda want to overclock my nexus too 1.7ghz but Im not sure that kernel can do it? I also want amazing battery life I get around 7.5 already so by no means is it bad
J
Sent from my Nexus 7 using xda app-developers app

I've got elementalx on my nexus 7 2013 : it works perfectly on 1.7ghz... And this kernel has some cool features like double tap to wake... For the battery, you can underclock but while you overclock just a bit, the battery life will be OK
So, flash it ! ?
Térence
Sent from my Nexus 7 using xda app-developers app

JackHanAnLG said:
Hey guys
Before rooting my tablet I want to know something. Whats the fuss about this specific kernel? I literally see it everywhere ( well done to the dev )
I kinda want to overclock my nexus too 1.7ghz but I'm not sure that kernel can do it? I also want amazing battery life I get around 7.5 already so by no means is it bad
Click to expand...
Click to collapse
I didn't know there was any kind of a fuss! I think that we are all lucky in the sense that we have multiple good choices for kernels on the Nexus devices and most others in general.
It goes without saying that any custom kernel is going to give you the ability to overclock and it just boils down to what the max MHz is that any specific device can handle. Not that I've tried it but I've seen claims of 1.9 MHz and higher (ElementalX) running fine but each device is going to be different and I personally don't see the point of overclocking that high. I've had mine at 1.7 and 1.8 MHz to run some benchmarks, try different governors (elementalX & ondemand) and get an idea about battery life at those frequencies. Did all that so I can get a comparison to what I see running 1.6 MHz which is what I use everyday, that plus the gpu is set at 450 MHz while using the ondemand governor for both cpu and gpu. I do have to say that my N7 ran very well at 1.7 and 1.8 MHz but "my" goal is to get the best combination of performance and battery life, for my use. I generally see 7- 10 hrs of screen on time which includes watching video and some gaming. Not using any third party apps to control the kernel, mostly default settings when using the aroma installer, slight undervolt for 384 MHz, I don't use DT2W or S2W,. Basically... it's just too easy to install the ElementalX kernel, not worry about having to dial it in and still see a noticeable improvement in performance and battery life. No fuss, no muss!

What are your settings?
!PimpedOutNexus7!

shaolinz said:
What are your settings?
!PimpedOutNexus7!
Click to expand...
Click to collapse
Aroma installer;
Set each core separately = no
Max Cpu Frq = 1620Mhz
L2 cache and bus = elementalx
Undervolt = 850 min
Thermal = run hot. Mine never gets hot at 1.6 MHz and this way you don't have to worry about thermal throttling.
Max GPU = 450 MHz
Gpu governor = ondemand
i/o scheduler = deadline.
Sleep/wake settings = None
Other settings = use stock ondemand settings. enable max screen freq, enable usb fastcharge, disable magnetic screen off, disable fsysnc, all other options unchecked,
---------- Post added at 06:51 PM ---------- Previous post was at 06:42 PM ----------
You can use the elementalx governor which does a great job and does improve battery life. In the other settings page leave "use ondemand governor' unchecked and check the box for "gboost." For gaming I personally like to leave mine set up with the ondemand governor, seems just a little bit smoother with less frame drops. You can try both to see which works better for you.

Thanks a lot in will let you know how it goes ....great help +1
!PimpedOutNexus7!

Hmmm feels like its running hot
!PimpedOutNexus7!