Undervolting my cpu

[rbogomolec]

I read a lot of stuff about this topic on several forums including this one, yet I want to make sure I understood it right. It's not that I'm scared to lower my voltage by -100mV, it's more that I want to understand the whole thing cuz I find it very interesting. So here are my questions:

1. Is it true that undervolting doesn't have negative side-effects?
2. I read that lowering the cpu usage in windows power settings from 100% to anywhere between 80-99% will also keep your laptop from overheating. So I was wondering if I should do both, underclocking + setting cpu to let's say 90%. Is that a good idea or would I be overdoing it then?
3. What about performance when undervolted? I read that you don't really lose on performance, yet I wonder how come. If I'm playing a game and my cpu temp gets to 75'C, will undervolting it allow me to play on the same quality settings but with a lower cpu temperature?

My laptop is an ASUS N550JX, i7 4720HQ, 8GB RAM, GTX950m 2GB
Btw, I play games on medium settings that's why I'm asking all of this. I understand that underclocking would be a stupid thing to do if playing on high or ultra settings.

Thanks in advance!

 

[Dunlop0078]

1. If it will run stable yes there are no negative side affects. If it's gets unstable you may get freezes and/or blue screens. No CPU is created equal your sample may be able to run stable at a lower voltage or it may not, only way to know for sure is to try.

2. Using a power saving setting in power options will likely not allow you to reach boost clock speeds, this will lower heat under load it will also reduce performance.

3. Performance will not change when undervolted assuming the CPU is stable at that voltage.

 

[geofelt]

The windows balanced power options behave differently when on battery vs. plugged in.
When on battery, your display brightness will be lowered and your maximum cpu performance will be lowered.
You will also run in integrated graphics.
These are done to conserve battery run time.
Of course, these options can be changed by you.
1. True. A processor will lower it's multiplier and associated voltage all the time when it has little to do.
2. Whenever the multiplier is lowered, it will take less voltage and consequent heat to run. If running plugged in, I would use the max performance setting. If heat is an issue, clean out the cooling passageways from dust.
3. A intel processor will slow down or shut off if it reaches a dangerous temperature. That is around 100c.

No reason not to experiment with the power settings. My thought is to not do so unless you are gaming on battery and need to extend your run time by lowering your performance.

 

[rbogomolec]

Let's say I find out that my cpu can run at -150mV and that it gets unstable at -155mV. Should I keep it then on -150mV or should I raise the value a bit, let's say to -130mV, just to keep it on the safe side?