AMD power management: CPU never under 2,9Ghz

[rohowsky]

Hi. I've managed to successfully install macOS Catalina on my build with Opencore. I've added the "AMD Ryzen CPU Power management" kext and the system runs stable and fine, but I've noticed that the CPU's clock never goes under 2,9Ghz on auto mode. Is there a way to make it automatically downclock under 1Ghz in idle?

My system has a Ryzen 3 3100 and a Gigabyte B550M DS3H mainboard.

 

[Shaneee]

Yes but be careful what you are doing as it can cause damage to your hardware. You need to add

 

[Aluveitie]

Ryzen CPUs can manage themselves very efficiently, usually you don't see major power savings by further lowering the CPU speed further.
What I noticed modifying P-states after booting (meaning outside of the BIOS) will get my clock out of sync...

 

[rohowsky]

Yes but be careful what you are doing as it can cause damage to your hardware. You need to add

And I guess that If I add manually further values to lower the CPU-clock, those values will be applied only when the AMD Power Management app is running. Is it correct?

Ryzen CPUs can manage themselves very efficiently, usually you don't see major power savings by further lowering the CPU speed further.
What I noticed modifying P-states after booting (meaning outside of the BIOS) will get my clock out of sync...

Ok. So are you suggesting to keep AMD power management with the standard settings, right?

 

[Aluveitie]

Those values are written to the CPU and persist until you either sleep/wakeup or reboot.

 

[rohowsky]

Those values are written to the CPU and persist until you either sleep/wakeup or reboot.

Ok. I won't change manually the values, but I've just checked the "low power state" box.

Another thing I've noticed is that the temperature in normal use (web browsing and office) constantly oscillates up and down between 44 and 58°C in a few seconds. I don't know if these values are 100% reliable, but it seems so, since the fans are constantly increasing and decreasing their speed. Is this normal?

 

[Aluveitie]

This pattern is not unusual with Ryzen, you can minimize the noticeable effect by adjusting your fan curve.

 

[rohowsky]

This pattern is not unusual with Ryzen, you can minimize the noticeable effect by adjusting your fan curve.

Thanks for the information

 

[MadMax1998]

I'd like to reopen this question. I'm on Big Sur 11.1 with a new 5600X on an X570 mobo. With AMDRyzenCPUPowerManagement.kext I seem to get no further than 25W minimum CPU power consumption, with temperatures hovering around 47°C.
However, in Windows 10 with AMD chipset drivers and the "Ryzen High Performance" power plan, AMD Ryzen Master shows me a consumption of only 3-8W when idling, with temperatures around 40°C. Also, the cores are reported to go into a "sleep mode" even though Windows task manager reports a clock of over 4 GHz.

I've found that in macOS the CPU never really idles and goes to sleep. The cores will hover at the highest speed step and only periodically go down to SS2 (never SS1). When I check the option in Power Gadget that's supposed to automatically clock the cores down, that rarely happens; basically only right after booting into macOS. As soon as I launch any application (and close it) the cores never calm down.

I'm not too bothered by it but I wonder what the point of "native" (UEFI-controlled) power management is when power is not really saved at all. And it seems that at least the CPU temperature has not decreased at all since I installed the kext; it was around 50°C before I had the kext running.

 

[Shaneee]

@MadMax1998 The thing is AMD CPUs were never meant to run macOS. This is the best we can achive currently. My 3600 idles around 28 - 32 with the kexts enabled.

 

[MadMax1998]

I was afraid of that, yeah. Thanks.

 

[Shaneee]

You could contact trulyspinach the creator of AMDRyzenCPUPowerManagement.kext and see if he has any suggestions.