AMD and Microsoft have finally acknowledged poor L3 cache performance in Windows 11, and a fix for the same is on the way in the form of a Windows update later this month. AMD also notes that CPPC2 may not schedule threads properly on preferred cores in Windows 11 and is investigating a fix.
https://www.notebookcheck.net/AMD-and-Microsoft-finally-acknowledge-poor-L3-cache-performance-and-CPU-scheduling-issues-with-Ryzen-processors-in-Windows-11-after-nearly-three-months-of-complaining.569990.0.html
Maybe this is why W11 stinks so bad on Zen2 CPU's and MSFT won't certify them. Once AMD releases the package one wonders if the performance will then be acceptable and MSFT changes their mind.
you are running slightly different memory??