MSI B350 P-state question

[Choda 996]

Hello when I turn on cool and quiet option in BIOS, new option pops up, and I can chose Pstate 1, 2 or 3. What is P state and which one should I chose?

 

[drea.drechsler]

Hello when I turn on cool and quiet option in BIOS, new option pops up, and I can chose Pstate 1, 2 or 3. What is P state and which one should I chose?

I am curious,too, what that PState option feature does exactly. It was an added selection in the latest BIOS for my board so I suspected it was for Ryzen 2000 series processors.

P-States are the performance or power levels the processor can operate at: P0 is the highest performance level, therefore the highest sustained, un-boosted, power consumption level too. It should be the stock rated performance level claimed in advertising. The processor will operate at lower states (P1 down to P6 or so) to save power when there isn't work to be done. Ryzen core boosting, including XFR and PBO, are done at 'hidden' PStates higher(lower) than P0.

In my un-overclocked system turning off Cool-N-Quiet disables P-State changes so it stays at P0 constantly. When I manually overclock it also disables Cool-N-Quiet but if I force it on it will stay at a higher PState(lower performance level) constantly.

What processor do you use? I have an R7-1700, Zen 1. Are you overclocking, or completely stock frequency?

 

[Choda 996]

Hello when I turn on cool and quiet option in BIOS, new option pops up, and I can chose Pstate 1, 2 or 3. What is P state and which one should I chose?

I am curious,too, what that PState option feature does exactly. It was an added selection in the latest BIOS for my board so I suspected it was for Ryzen 2000 series processors.

P-States are the performance or power levels the processor can operate at: P0 is the highest performance level, therefore the highest sustained, un-boosted, power consumption level too. It should be the stock rated performance level claimed in advertising. The processor will operate at lower states (P1 down to P6 or so) to save power when there isn't work to be done. Ryzen core boosting, including XFR and PBO, are done at 'hidden' PStates higher(lower) than P0.

In my un-overclocked system turning off Cool-N-Quiet disables P-State changes so it stays at P0 constantly. When I manually overclock it also disables Cool-N-Quiet but if I force it on it will stay at a higher PState(lower performance level) constantly.

What processor do you use? I have an R7-1700, Zen 1. Are you overclocking, or completely stock frequency?

Everything is stock, auto voltage, no OC at all. Ryzen 2600x. When I disable cool and quiet Pstate option in bios isnt visible anymore and can not be changed, but when I enable it Pstate option shows up. I guess "stock" option for it is 0.

 

[drea.drechsler]

Everything is stock, auto voltage, no OC at all. Ryzen 2600x. When I disable cool and quiet Pstate option in bios isnt visible anymore and can not be changed, but when I enable it Pstate option shows up. I guess "stock" option for it is 0.

Cool-n-Quiet is AMD's proprietary name for this PState system. I think Intel's is Speed Step. They do work differently, but accomplish the same thing. And AMD has changed and refined it a lot with Ryzen vs. FX and Phenom before that. It used to be seriously important for keeping a quiet system but now it enables people to be energy sipping as possible, yet have sufficient processing power available if needed.

You could try changing the selection from 0 to 1 or 2 and rebooting. It can't hurt and you can always re-boot to change it back.

Just on a pure guess it may do one of two things:
1: limit the highest sustained performance level to the one chosen. So instead of sustained operation at P0 (3.6Ghz for 2600x) with setting at 1 it may limit sustained operation to P1 (maybe 2.7Ghz or so). It may then treat 3.6Ghz like a boost state, just popping up to it for short bursts.

Or
2: maybe it will never go any lower than a P1 (2.7Ghz or so) state.

 

[Choda 996]

Everything is stock, auto voltage, no OC at all. Ryzen 2600x. When I disable cool and quiet Pstate option in bios isnt visible anymore and can not be changed, but when I enable it Pstate option shows up. I guess "stock" option for it is 0.

Cool-n-Quiet is AMD's proprietary name for this PState system. I think Intel's is Speed Step. They do work differently, but accomplish the same thing. And AMD has changed and refined it a lot with Ryzen vs. FX and Phenom before that. It used to be seriously important for keeping a quiet system but now it enables people to be energy sipping as possible, yet have sufficient processing power available if needed.

You could try changing the selection from 0 to 1 or 2 and rebooting. It can't hurt and you can always re-boot to change it back.

Just on a pure guess it may do one of two things:
1: limit the highest sustained performance level to the one chosen. So instead of sustained operation at P0 (3.6Ghz for 2600x) with setting at 1 it may limit sustained operation to P1 (maybe 2.7Ghz or so). It may then treat 3.6Ghz like a boost state, just popping up to it for short bursts.

Or
2: maybe it will never go any lower than a P1 (2.7Ghz or so) state.

What's default P? 1/2/3 ?

 

[drea.drechsler]

What's default P? 1/2/3 ?

I'd say P0 but I'm not sure: whatever it was when you first entered the field is a good bet. When experimenting with BIOS settings you should always have a saved profile AND note what a setting is when you first enter the field.

I never SAVE bios settings if I'm popping in and out of fields examining them: that because i may accidentally change one unknowingly. I'll quit without saving and reboot if I find one setting I want to change.

If you did change something you may have to reset the BIOS (using CLEAR CMOS SETTINGS jumper) to be sure everything is in defaults.

You could also try typing AUTO in the field. That frequently works in my motherboard.