Zen 3 core loading background vs foreground?

[Cyber-Mav]

noticed some very interesting behaviour on how my cores are being loaded on the 5900x, running windows 10.

screenshot:

so i thought id test my boost clocks and voltages while running super pi and noticed some very interesting results. i had a web browser open with 1 tab on a website and hwinfo open doing the monitoring, what i saw was surprising.
When super pi is testing and iv got focus on the window itself my fastest core is used and i get the highest boost (screenshot highlighted in green border). however, when i clicked on the web browser to bring it into the foreground and now super pi is in the background and not a focused window i noticed in hwinfo that the load had now shifted to my weakest core which boosts the least!!! ((screenshot highlighted in red border).
clicking on the taskbar icon to bring super pi to the foreground and be in in focused window straight away shifts it back to the fastest cores and highest boost and clicking back on browser window with put the load back onto the slowest core??

anyone else noticed this behaviour where if a single thread task is in the foreground it uses maximum boost but if its in the background and not the focused window it shifts to the slower core?

 

[Cyber-Mav]

Odd, does this happen on intel cpus that use ecores? Would a high cpu usage task thats put to background jump onto the ecores?

 

[Cyber-Mav]

Yes, the same happens to intel. That is a good thing, cause you can choose from windows settings how you want it to behave. You can eg play a game while rendering on the background with virtually no performance penalty by selecting foreground apps in the windows setting,since it will keep the rendering on the ecores.

Where is this setting? Is it in the power plan options?

 

[Cyber-Mav]

Ahh iv seen that option didnt think it actually did anything lol.

 

[Cyber-Mav]

Is the Intel system running Windows?

only intel systems i have is my server running a haswell xeon and a hp mini pc with 8th gen i-something cpu. they run windows but not tested anything like this on them.
the ryzen 5900x i have did this behaviour which i found to be fascinating. will have to see how power consumption is if browser uses ccd0 and background app uses ccd1 vs both being on the same chiplet.