Related
i have used the search and not found any solid info
what are the benefits of it if any
I haven't heard of people undervolting their fone, although i haven't looked to much.
This would mean though reducing the power that the CPU gets. I would imagine this increases battery life among other things.
Your right about what it is, but almost every custom rom/ kernel is undervolted in development section.
Sent from my HTC Desire using XDA App
Undervolting means, the CPU (or hardware in the phone) gets lower voltages, thus saving more battery & not loosing performance.
Undervolting is a process which reduces the excess "voltage" given to the CPU using a software. This is widely used as a cooling solution and in my opinion more effective than any other cooling solution available (thermal paste, cooling pad, etc) at NO cost. Undervolting will NOT compromise performance at all. Underclocking and Overclocking (clock speeds) is whats responsible in regards to performance. Benchmarks will also prove that performance remains the same.
Click to expand...
Click to collapse
Not excess voltage but fully, manufacturer guaranteed, stable Core voltage to lower guesswork voltages which may or may not work and may or may not cause data loss/corruption.
------------------------------
- Sent via HTC Desire -
A cpu needs power for every 'clock cycle'. 1Ghz means there are a billion per second. IF you lower the voltage, there is less power used. But if you lower it too much, the cpu wo'nt be able to 'cycle its clock'...
So undervolting doesn't affect performance, since the cpu remains on 1Ghz. It decreases the power used, so you get better battery life.
Every single cpu is different, so HTC has chosen a default voltage that (shoud) work on all phones they sell. But your particular cpu could be able to work at a lower voltage. It's just a matter of trail and error. Decrease the voltage until the cpu stops working, then higher it a bit. That way you've undervolted your cpu so it uses the least power.
koenvbeek said:
A cpu needs power for every 'clock cycle'. 1Ghz means there are a billion per second. IF you lower the voltage, there is less power used. But if you lower it too much, the cpu wo'nt be able to 'cycle its clock'...
So undervolting doesn't affect performance, since the cpu remains on 1Ghz. It decreases the power used, so you get better battery life.
Every single cpu is different, so HTC has chosen a default voltage that (shoud) work on all phones they sell. But your particular cpu could be able to work at a lower voltage. It's just a matter of trail and error. Decrease the voltage until the cpu stops working, then higher it a bit. That way you've undervolted your cpu so it uses the least power.
Click to expand...
Click to collapse
Very sensible answer..Thanks
koenvbeek said:
A cpu needs power for every 'clock cycle'. 1Ghz means there are a billion per second. IF you lower the voltage, there is less power used. But if you lower it too much, the cpu wo'nt be able to 'cycle its clock'...
So undervolting doesn't affect performance, since the cpu remains on 1Ghz. It decreases the power used, so you get better battery life.
Every single cpu is different, so HTC has chosen a default voltage that (shoud) work on all phones they sell. But your particular cpu could be able to work at a lower voltage. It's just a matter of trail and error. Decrease the voltage until the cpu stops working, then higher it a bit. That way you've undervolted your cpu so it uses the least power.
Click to expand...
Click to collapse
How would one go about under volting .i have tried everything suggested to me and nothing really seems to make a difference
Sent from my HTC Desire using XDA App
Most kernels are undervolted and unless you can compile the kernel for yourself you are stuck with the values given by the creator. There are two exceptions for this, HAVS kernels which automaticly chose a voltage depending on temperature and some other stuff and SVS kernels with snq-'s volt selection interface (found in Leedroid and maybe some other kernels/roms).
So what exactly have you tried and what did you expect to see? Because the difference won't be that noticeable.
TheGhost1233 said:
Most kernels are undervolted and unless you can compile the kernel for yourself you are stuck with the values given by the creator. There are two exceptions for this, HAVS kernels which automaticly chose a voltage depending on temperature and some other stuff and SVS kernels with snq-'s volt selection interface (found in Leedroid and maybe some other kernels/roms).
So what exactly have you tried and what did you expect to see? Because the difference won't be that noticeable.
Click to expand...
Click to collapse
I have tried battery calibration, using app watch dog to let me know which apps are using excessive CPU. Putting my brightness down to 10%, making sure not everything is synced, the only thing synced is beautiful widgets every 4 hours. And just about everything else that has been put forward to me. Here's another example I just taken my phone off charge at 100% and wrote this and I'm now at 73 %. And its only taken2 mins to write
Sent from my HTC Desire using XDA App
adz63 said:
I have tried battery calibration, using app watch dog to let me know which apps are using excessive CPU. Putting my brightness down to 10%, making sure not everything is synced, the only thing synced is beautiful widgets every 4 hours. And just about everything else that has been put forward to me. Here's another example I just taken my phone off charge at 100% and wrote this and I'm now at 73 %.
Sent from my HTC Desire using XDA App
Click to expand...
Click to collapse
So in short you havent tried any kernel with undervolting at all!
Well that all has nothing to do with undervolting, but (extra) undervolting will not fix the drain problem you have.
Do you use setCPU cause your sig says you run at 1113MHz, which cause higher consumption. Also did you set your wifi sleep policy to never(setting-wireless and network-wifi settings-press menu-advanced-wifi sleep police).
At the moment I have the havs kernel that comes with oxygen 2.0 rc6. I have posted another topic about is the kendal good for battery life etc and no1 has told that another kendal would make anything better
Sent from my HTC Desire using XDA App
TheGhost1233 said:
Well that all has nothing to do with undervolting, but (extra) undervolting will not fix the drain problem you have.
Do you use setCPU cause your sig says you run at 1113MHz, which cause higher consumption. Also did you set your wifi sleep policy to never(setting-wireless and network-wifi settings-press menu-advanced-wifi sleep police).
Click to expand...
Click to collapse
@TheGhost1233, how exactly does one decide which kernel suits us best..
Eg: I see two undervolted kernels (I think) at 875 and 925 mV. I have no idea how to decide. Trial and error?
Froyo Kernel [email protected] min
Froyo Kernel [email protected] min
@droidzone Yes trial and error. The mentioned voltage is the lowest the cpu will get at 245MHz. Not all devices are stable with 875mV (you will know if your phone freezes up) so then you move up to the 925mV min. Other than the voltage there is no difference between 875mV or 925mV.
With the HAVS kernels it can take a while before you notice the freezes cause the voltage is dynamic, so be careful if you need your phone as a alarm clock.
I am new to android phones. And i have no experience about overclock.
Will my cpu easily break down due to keep overclocking?..
Honestly, i seldom change my cell phone model, i want my defy can stay a life at least 1.5yr.
i think overclocking can't really damage your phone, voltage can. so i suggest you keep the voltage around [email protected] (default is [email protected], so this should be fine), and if the phone doesn't hang or reboot, you're good to go but you could try lowering vsels, you know, the lower the voltage, the lower the power consumption, the heat and the chance to fry your cpu but i'm not sure!
Yep, 1 GHz is safe, I'm using [email protected] as well, and the CPU is capable to run easily at [email protected] continuously. The leaked Gingerbread ROM from Motorola uses 1GHz as well, so don't worry, you just have to find the safe vsel settings.
thanks for replying, i m currently using 1GHz @ 58 .. Everything is alright
Should I make the voltage as low as possible?
yeah, just to lower the power consumption and temperature, but it isn't necessary.
Can you share your voltage setting please..?
I do the stability test and it gets successful run for 5min then this means the setting is okay?
i don't overclock, just undervolt, here are my settings (with setvsel):
800MHz - 45vsel
600MHz - 30vsel
300MHz - 18vsel
up_threshold: 90%
actually if you wanna make absolutely sure your device is stable, you should run it like for an hour. but if it runs for 5 minutes without error that's quite okay, you shouldn't have problems with those settings
Thanks so much, i m trying to lower my voltage setting.
Besides, i want to ask about the battery temperature, what is the maximum temperature before getting damage to the cell? I usually goes up to 37~39 degree celsius.. is it normal?
mine is usually around 29-32 °C, but i have it undervolted, so idk. but 37-39 seems a bit high, that means the cpu temp is way over 40 degrees, you should check it out!
EDIT: tried stress testing for 20 minutes with [email protected], it went up to 35°C, so you should definitely find out what's wrong with your device!
I actually underclocked to 600MHz, since I couldn't see a big difference even at 1200MHz in normal usage. A Pentium3 at 4Ghz will still not perform as well as a slower clocked new CPU for example, CPU design is more important - what instructions it supports.
Battery life is more imprtant to me and heat is very bad for Li-ion batteries too.
Also I found changing the CPU governor to "interactive" made a difference in GUI responsiveness and I have had less stuttering.
nisamtetreb said:
I actually underclocked to 600MHz, since I couldn't see a big difference even at 1200MHz in normal usage. A Pentium3 at 4Ghz will still not perform as well as a slower clocked new CPU for example, CPU design is more important - what instructions it supports.
Battery life is more imprtant to me and heat is very bad for Li-ion batteries too.
Also I found changing the CPU governor to "interactive" made a difference in GUI responsiveness and I have had less stuttering.
Click to expand...
Click to collapse
so, what's your standby lifetime after underclocked cpu?
I can see the performance improved when i was watching flash video on browser. But honestly, i dont think there are anymore huge difference after overclocking..
But as the battery life still remains quite well, i will still keep overclocking to 1GHz.. Isn't it a good idea?
nisamtetreb said:
I actually underclocked to 600MHz, since I couldn't see a big difference even at 1200MHz in normal usage. A Pentium3 at 4Ghz will still not perform as well as a slower clocked new CPU for example, CPU design is more important - what instructions it supports.
Battery life is more imprtant to me and heat is very bad for Li-ion batteries too.
Also I found changing the CPU governor to "interactive" made a difference in GUI responsiveness and I have had less stuttering.
Click to expand...
Click to collapse
lol... What happend to HD and THD games... Did u try playing them at 600mhz??
Overclocking to 1 GHz with the right voltage values seems to be absolutely no problem for Defy.
BTW, does anyone know whether it's possible to set scaling governor to "Interactive" mode under Froyo? Gingerbread kernel let me set it, but I haven't found the way under Froyo.
Battery life was a little bit better, the display and 3G always draw a lot of power.
Standby time got better, but I don't use very low vsel any more due to errors in YouTube and dropped connection of radio streams.
Before I used 300-600-800 at 20-30-48, this was very stable in stability test, but for example Youtube would start showing "error playing video". After I increased vsel, it went away.
I mostly did it to lower temperature, optimal temperature for li-ion is around 25°C according to Wikipedia I think.
I don't play 3d games, they would benefit the most from overclock I believe.
Angry birds RIO for example would stutter for a second or two after a level loaded, but it would become as smooth as at higher clocks, when I wait for a second.
I hope flash gets better, when hardware acceleration gets enabled in Quarx's CM7.
I was running [email protected] for a month straight. No issues at all. The highest my temp reached was 112F after playing games for about an hour straight. I now just run it at [email protected], and it's plenty fast for me. I did some "testing" with all the options in SetVsel. It's not science sound, but if you use the Gingerbread Icon in the notification bar, and are running at stock (800 speed) you will notice when the CPU maxes out it doesn't even reach full capacity. I found Words with Friends to really use the CPU, and at 800 it pings the meter in the orange (The notification icon shows green, orange, and red for "zones"). If I overclock it at 1000 or above then the meter goes into the red. I don't know the exact number it switches from orange to red, but being at stock 800 is well below what the chip can really do since it doesn't even max out the meter. I hope I didn't confuse anyone. It makes sense to me.
weird...my cpu at any game reach the 800mhz
yet even in normal situations like browsing through the files on the phone it reaches 800mhz
and also despite the values i use in setvsel are not high(which is:
24 @ 300
34 @ 600
48 @ 800
)
the phone still reaches maximum 38C when i play games and if i set the value in the third vsel the games starts to hang!!
seems like i am the only one who have these problems..but why
anyone have any idea
im running stock arabic froyo btw
if someone can confirm to me that i can keep Arabic language if i installed another rom using custom restore in nandroid then i would be using prays or official 2.3 but no one answered me about that
anyway the important thing is anyone knows why my cpu temp is always high?
Well ambient temperature is important too. If it is 30°C where you live and your phone's temperature is at 35°C I'd say you are good. If the outside temperature is 10°C and your phone is dat 40°C I'd say there is something wrong (unless you were playing games or watching a movie).
in my opinion, it is definitely safe that you overclocking to the leaked moto level.
however, the voltage is still a mystery.
there's no constant conclusion about this.
i'm using [email protected], [email protected], [email protected], and it works fine for me
I'm getting really annoyed. No problems clocking up to 1100mhz with stock voltage (58). But changing the voltage settings, even slightly, makes the phone more or less unstable.
I'm wondering if anyone's undervolted and to what values.
I'm also wondering waht the deafult values are and if they change per kernel.
Is there a way to disable SetCPUs undervolting settings?
Has anyone improved battery life with profiles? On the Eris this was the only way to get usable battery life.
Or not. I gave up undervolting after I actually compared battery life at stock values vs undervolted (on my old phone, sgs4g) and discovered it does nothing for battery life.
Edit: undervolting "might" marginally increase standby battery life, but considering how good this phone already does... it certainly won't increase actual screen on usage.
Sent from my Galaxy Nexus using xda premium
Depends how low you under volt. Got more battery life, maybe about an hour, after finding optimal battery life on my gfs Gnex.
If you don't under volt correctly, of course it won't improve battery life.
From my sexy white, Nocturnaled HTC One X
If you're not overly comfortable with undervolting, then using one of the many kernels with Smart Reflex will do a mild undervolt for you. If you are comfortable, then the only way to find numbers good for your phone is to try and test. I tweaked mine down to the point that I was occasionally getting hot boots when the screen was off and media was playing. Tweaking the numbers back up added the needed stability. Even little things like kernel or ROM revisions can change what voltage is or isn't stable. Another example is that when I updated my Jellybro CM10 version the other night, along with updating leankernel from 4.1.0exp3 to 4.2.0, I had to increase a few of my voltages to avoid hot boots.
Just for example numbers, here are mine:
Code:
1350MHz -- 1200mV
1200MHz -- 1150mV
920MHz -- 1050mV
700MHz -- 950mV
350MHz -- 825mV
These numbers will vary from device to device and even between ROM/kernel combinations, so don't use them as hard fact.
Thanks. On a phone like this it might not make a huge difference but on the Eris (Where stock battery life could sometimes be 6 hours if you actually used your phone) an undervolted kernel with setcpu could turn those 6 ours into 48.
Thanks Cilraaz, I'll try those voltages out and benchmark a bit to see if they're stable for my system.
Two things I can say for sure:
1. you will have very limit battery gain by undervolting with Gnex, no matter how low you try.
2. undervolting will bring some stable issue if you get too low, like lose signal and reboot.
I am using Kernel Franco GPU 384 Stock rom on my 4.1.1 and did undervolting
Current configuration:
384Mhz
950mv
------------
729Mhz
1050mv
-----------
1036mhz
1125mv
----------
1228mhz
1275mv
-------------
I did not change the frequencies of overclocking, because I'm not using them.
I felt an improvement in battery consumption unless the unit is heating up.
Just curious - what kind of profiles are you using? I have a "Screen off" that's 350min and 700max. I figure that's fast enough f someone calls me.
I've read many times undervolting isn't worth it.
Hungry Man said:
Just curious - what kind of profiles are you using? I have a "Screen off" that's 350min and 700max. I figure that's fast enough f someone calls me.
Click to expand...
Click to collapse
I'm using the following with SetCPU: default (1350MHz-350MHz), charging, CPU temp > 64, and battery < 35%.
If you're using a kernel and governor that support hotplug, then you likely don't want to use a screen off profile. The combination of the two can tend to cause sleep-of-death or hot boots.
I Am Marino said:
I've read many times undervolting isn't worth it.
Click to expand...
Click to collapse
Most people don't want to spend the time to do it right.
I'm actually not used to the new kernels. I haven't messed with my eris in about a year and back them there was "smartass, on demand, performance," and some other one that clocked down instead of up
Can you explain th escreen off profile causing issues? I don't even know what hotplug is lol I've been out of Android for a long time.
Hungry Man said:
Can you explain th escreen off profile causing issues? I don't even know what hotplug is lol I've been out of Android for a long time.
Click to expand...
Click to collapse
Hotplug disables one of the CPU cores when the screen is off. Some governors, like hotplugx, will also attempt to disable a CPU core during periods of low CPU usage. For some reason, this combined with a screen off profile can cause some problems. I assume it's because of the "screen-off-max-freq" that Imoseyon mentions in the quote below.
Personally, I prefer the interactivex governor with leankernel by Imoseyon. From his kernel thread:
With interactiveX V2 (for gnexus), things are a bit different, since gnexus has built-in support for screen-off-max-freq for all its governors. I took the new interactive code in gnexus, added early_suspend support (screen off/on trigger), and then added logic to the code so the governor uses the phone's built-in hotplugging capability to turn off cpu1 when screen is off (and then turn it back on when screen comes back on). Cpu1 goes offline entirely - no idle, no sleep.
Click to expand...
Click to collapse
I think undervolting helps - my phone is running 728 - 1228 using the interactive governor, with voltages of 600 mV, 700 mV, and 800 mV (728 MHz, 1036 MHz, 1228 MHz respectively) and I haven't had any issues so far. I know there are some reports that say undervolting doesn't help much, but those are when people undervolt by like 50 mV, whereas here I'm going like 400 mV under lol. (Yes, smart reflex is off).
Thanks Cilraaz. Good to know.
So turning the screen-off profile could improve things? Honestly, my system does fine at 350mhz with screen off. Turning a core entirely off would probably help though.
If I use hotplugx governor that would disable one core when the screens off, right?
Hungry Man said:
If I use hotplugx governor that would disable one core when the screens off, right?
Click to expand...
Click to collapse
Hotplugx will disable a core when the screen is off or when there is low system load. Depending on your kernel/governor choice, other governors may do it also. On leankernel, for instance, interactivex will disable a core when the screen is off, but not on low system load.
Ok, thank you.
I haven't done any comparisons of before/ after since I undervolted/ underclocked first thing. But I was browsing for hours while listening to music while talking to a friend with GTalk. talked for about 1.5 hours with someone, Left it on overnight (10 hours), woke up, used it to talk (voice to text) to someone via GTalk, and it's 3:25PM right now and I still have a fair amount of battery life left.
I'd heard mixed things about the battery on this so I'm happy.
My voltages:
1650: 1300
1520: 1250
1350: 1175:
1200: 1125
920: 1000
700: 925
350: 900
I stress tested each one without a crash.
So I tried to underclock my One X to around 640 MHz and it was running VERY smoothly and stable with only 2 cores active. I was using the ViperX 2.2.1 ROM and the Kernel was the no OC NCX 0.99a. The battery life wasn't bad, but has anyone tried underclocking to 1 GHz or lower? If so, how is the battery life and what kernel and ROM did you use?
With SetCPU you can change the max. CPU, but why should you? When the phone doesn't need much processor power, it just scales down by itself.
So, it already has the best underclocker there is.
Mayby you could try undervolting to save even more battery, but that means the CPU can be somewhat less steady.
im trying to get my head around UVing / UCing my HOX. is there any guide around? im trying to search through the forum but still no luck.
ricopoetra said:
im trying to get my head around UVing / UCing my HOX. is there any guide around? im trying to search through the forum but still no luck.
Click to expand...
Click to collapse
underclocking means the CPU runs slower so should use less battery but slower CPU speeds also means to takes longer to preform tasks which could use more battery, check on google most places say its not worth it as that battery saved is tiny and not worth the drop in CPU performance.
undervolting however lowers the voltage that CPU uses while working this does save power and also lowers heat (less voltage less heat) but if you lower it to much then the CPU becomes unstable due to lack of power and well crashes and restarts the phone in most cases.
to get the best out of undervolting you need to lock the max CPU speed to each step (CPU speed, 300mhz, 600mhz and so on) and slower the voltage and then run a bench mark (like antutu) and see if its stable, if it is you lower the voltage again and repeat until it crashes at which point you have found the lowest voltage that the clock speed can handle so you jump up a voltage then more on to the next speed.
it takes along time but that would get you the best undervolt your phone and hardware could handle.
or you can just use the global to lower the voltage for every speed, this is much faster and much less time consuming but you don't get the most out of it.
for this you basically drop the voltage then use your phone for different things; browsing, games, benchmark and see if it crashes if not lower again till it does then go back up a step.
thanks for explaining. I'm getting some of the points that I missed Awhile ago. I guess I'm going to try the longer way of doing it.
Sent from my White HOX JB PA 2.10
Have a question regarding min CPU speed vs voltage. I run task's Roman with stock kernel. My phone is not stable unless I up the voltage on the CPU clock at both the 189 and 378 speeds to 925mv.
So here's the question... since both speeds use 925mv, wouldn't it make more sense just to leave the min CPU speed at 378? Seems to me the faster min speed would process faster allowing the phone to go into deep sleep faster and saving battery.
Thoughts?
192 and 384, you mean?
Personally, I prefer my min at 192 not cos of mV difference, but cos it keeps my phone lots cooler when at min speeds.
I asked a similar question with no response. mine goes down to 81mhz and stays stable but a higher clock speed uses the same voltage so I thought just run the higher one. unless deep sleep is consistent then it shouldnt matter. but for cases like bluetooth or music streaming the higher speed might seem better. but the more heat thing must cause more battery usage I would think
s384 said:
I asked a similar question with no response.....
....more heat thing must cause more battery usage I would think
Click to expand...
Click to collapse
Looks like some thread lost with time...
More heat isn't good... heat is nothing but energy dissipated... and that means energy lost... So more heat is an indicator that you are kinda pushing your CPU to work hard and harder the work, more the battery utilized.
The voltage consumption of a CPU is calculated by f*V^2. So to answer the question, even if two frequencies share the same voltage, the lower frequency will still consume less power than the higher frequency.
Sent from my SGH-I747 using xda app-developers app