[SOLVED] which cpu c state and p state should i use?

eziowar

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Jun 11, 2015
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hi, my cpu i5-4670k, gpu - 1050ti, mobo- gigabyte z87x-ud3h, bios version F10b. in my bios i have these cpu states options available - c states - c1e,c3,c6/c7 and p states- eist. can u plz tell me among those whichcpu state or states combinations should i enable for maximum power saving without degrading stability and performance?
 
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Solution
Eist is your speed step, it slows down the processor and lowers voltages when you are at idle. Definitely enable that.
C1e, C1, C2, C3 are mild sleep modes, they do most of the sleep shutdown work and should be enabled.

C4-C6 will depend on your psu and bios. You have a Haswell cpu, which enabled ultra heavy sleep modes with very little actual voltage used, it's so low that many older power supplies are incapable of waking up afterwards. It's almost like the pc goes into a coma, still on, just can't wake it up. If you have the old style psu, it'll have large green/white lettering CS650. Don't use C6/C7 with that psu. If that means your bios stops at C3, and you don't use C4+, then so be it.

If you have the...
You should be on BIOS F10b(yes it's Beta but you should be on it for the sake of your processor). I'd leave them on Auto unless you're overclocking on them, in which case speedstep should be enabled, speaking of which, what is the make and model of your PSU?
 
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You should be on BIOS F10b(yes it's Beta but you should be on it for the sake of your processor). I'd leave them on Auto unless you're overclocking on them, in which case speedstep should be enabled, speaking of which, what is the make and model of your PSU?
thank you for replying, my psu is corsaior cs650 . i did flashed my bios to f10b
 
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hi, my cpu i5-4670k, gpu - 1050ti, mobo- gigabyte z87x-ud3h, bios version F10b. in my bios i have these cpu states options available - c states - c1e,c3,c6/c7 and p states- eist. can u plz tell me among those whichcpu state or states combinations should i enable for maximum power saving without degrading stability and performance?

P-state adjustments are put into the BIOS for people doing extreme over clocking on liquid nitrogen...I wouldn't mess around with those settings unless you're positive on what they do and why you're adjusting them. Random p-state settings can and will lead to unpredictable clock speed issues with your cpu....just leave it on auto.
 
Eist is your speed step, it slows down the processor and lowers voltages when you are at idle. Definitely enable that.
C1e, C1, C2, C3 are mild sleep modes, they do most of the sleep shutdown work and should be enabled.

C4-C6 will depend on your psu and bios. You have a Haswell cpu, which enabled ultra heavy sleep modes with very little actual voltage used, it's so low that many older power supplies are incapable of waking up afterwards. It's almost like the pc goes into a coma, still on, just can't wake it up. If you have the old style psu, it'll have large green/white lettering CS650. Don't use C6/C7 with that psu. If that means your bios stops at C3, and you don't use C4+, then so be it.

If you have the newer design psu, it will have black/grey design and you can use all the sleep states as those psus are Haswell capable.
 
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Solution
Eist is your speed step, it slows down the processor and lowers voltages when you are at idle. Definitely enable that.
C1e, C1, C2, C3 are mild sleep modes, they do most of the sleep shutdown work and should be enabled.

C4-C6 will depend on your psu and bios. You have a Haswell cpu, which enabled ultra heavy sleep modes with very little actual voltage used, it's so low that many older power supplies are incapable of waking up afterwards. It's almost like the pc goes into a coma, still on, just can't wake it up. If you have the old style psu, it'll have large green/white lettering CS650. Don't use C6/C7 with that psu. If that means your bios stops at C3, and you don't use C4+, then so be it.

If you have the newer design psu, it will have black/grey design and you can use all the sleep states as those psus are Haswell capable.
thank you, this is my psu - https://www.corsair.com/us/en/Categ...Supply-Units/cs-series-config/p/CP-9020077-NA
should i use C6/7?