- Joined
- Aug 19, 2010
- Messages
- 527
- Motherboard
- Gigabyte Z390 Designare
- CPU
- i9-9900KF
- Graphics
- UHD 630 & Radeon VII
- Mac
- Mobile Phone
Well the number and value of p-states will depend on several factors and is chosen by the appleintelcpupm driver. The number of states appears to depend mostly on the system definition, whereas the values seem to have something to do with your CPU clock speed and how many states are defined in your SSDT. if you want broader states you should try removing p-state definitions from your SSDT that are above the values you are actually using since they are never used but appear to skew the drivers choice of p-states. In my case i use macmini5,1 definition, have 16-43 defined in my SSDT and have an overclock of 4200mhz. I regularly observe p-states of 16, 29 and 42 and more occasionally hit 36 and 27. This seems like a reasonable spread to me.
Also please se below for more OC info that i am copying and pasting from my post in another thread as it is rather important for people trying to achieve higher speeds:
i had some interesting experiments RE getting my system back to full 4.2ghz OC. moving to 43x 43x 43x 42x caused the same p-state kernel panic at boot that running 42 42 42 42 does. So i had to add another entry to SSDT for the 43x state (even though this state never occurs in OS X) after that everything booted fine and i was hitting 42x max with all the normal in between states. pretty cool. Except my system starting locking up frequently. no kp, just totally frezzes/ locks up and usually within a minute or 2 of boot, so its happened fast and consistently. Looking back at the original post it mentioned gigabyte removed multi step load line calibration and that you had to adjust your vcore in order to achieve certain OC. In fact i think my system locked once even at 41x max but after hours of usage and i thought it was a fluke. but for some reason when using an SSDT and full p-states the system can become unstable even if it was working perfectly at 42x with only top and bottom p-states before.
Well the solution is simple enough. You have to adjust your voltage settings. change the vcore from "auto" to "normal". this unlocks the dynamic vcore setting below it which i put at +0.150v. It is possible you will need more or less depending on your CPU and overclock. the original poster suggested +0.200v for achieving 4.6ghz for instance. Once you have set an appropriate dynamic vcore setting and put an SSDT.aml that includes definitions for all the needed states you end up with full p-states and full overclock in OSX at 100% stability.
Cheers,
g\
