Originally Posted by Dr.Molestratus
You are confusing undervolt with underclock. UC is a proven way to increase battery, but it directly makes the CPU run slower. UV will make the CPU/GPU/RAM receive less milivolts, and it will only increase battery, and not decrease performance. The thing with UV is that if the CPU at any given time does not get enough power, it can't perform a given task, and your phone will reboot.
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I'm not Confusing undervolt with underclock.
Undervolting can and does reduce performance if you go too far. (Not far enough to cause reboots)
Underclocking is not a proven way to increase battery, in fact it's quite controversial.
It's called race to idle.
Pretty much all processors have great power savings at idle speeds.
By lowering the clock speed common tasks and background processes take longer to perform. Thus keeping the cpu at a higher clock rate (using more mv) for longer and overall using more battery than what it would have done at a higher speed.
From my own tests -150 mv undervolt resulted in slower and sometimes even laggy performance. -100 is great
Underclocking to 1ghz shortened my average daily battery life by nearly 2 hrs compared to running at stock 1.5
Say what you like about stats but these are the results I found from actual usage
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