Question How am I getting max speeds with PBO off ?

[flyz]

I have a Ryzen 5600. With PBO enabled I get like 4325mhz on fastest core in Cinebench. With PBO disabled I get 4192mhz. But on TestMem5 with PBO disabled I get 4442mhz and PBO enabled I get 4417mhz. Why am I able to get max clock with TestMem5 with PBO disabled and also slightly faster than PBO enabled?

 

[pete_101]

I have a Ryzen 5600. With PBO enabled I get like 4325mhz on fastest core in Cinebench. With PBO disabled I get 4192mhz. But on TestMem5 with PBO disabled I get 4442mhz and PBO enabled I get 4417mhz. Why am I able to get max clock with TestMem5 with PBO disabled and also slightly faster than PBO enabled?

TestMem5 isn't a CPU test, it tests your memory speed, so it's just reporting the random high spikes your CPU reaches with little load on it....it's easier for your CPU to run faster when it's not having to do much work.

PBO is for when your CPU is under load, especially all cores, it sets frequency based off temperature and power limits. With it turned off, your system will slower under heavy load as it uses pre determined defaults to keep the system safe, which are lower than what PBO sets for the same work load.

 

[flyz]

TestMem5 isn't a CPU test, it tests your memory speed, so it's just reporting the random high spikes your CPU reaches with little load on it....it's easier for your CPU to run faster when it's not having to do much work.

PBO is for when your CPU is under load, especially all cores, it sets frequency based off temperature and power limits. With it turned off, your system will slower under heavy load as it uses pre determined defaults to keep the system safe, which are lower than what PBO sets for the same work load.

I see. Do you know if that random rebooting issue with PBO enabled always results in a WHEA error log? I had PBO enabled and yesterday it randomly rebooted and Event Viewer showed a WHEA error. Today it randomly rebooted but there was no WHEA error. Not sure if it's PBO or some new hardware problem. I'm going to disable PBO for awhile and see if it still happens.