First post-launch update for Windows 11 causes more performance issues on AMD CPUs

Laurent Giret

Amd Ryzen Cropped
Following the official release of Windows 11 on October 11, AMD has acknowledged that the new OS may cause some performance issues on PCs with compatible Ryzen CPUs. The chipmaker identified an L3 cache latency issue as well as another issue related to AMD’s CPPC2 “preferred core” technology, and the impact on performance can go up to 15% in some games.
AMD is currently working with Microsoft to address these issues in a future Windows 11 patch expected to be released later this month. In the meantime, though, yesterday’s first post-launch update for Windows 11 has apparently made things worse according to analysis from TechPowerUp.
“In our own testing, a Ryzen 7 2700X “Pinnacle Ridge” processor, which typically posts an L3 cache latency of 10 ns, was tested to show a latency of 17 ns. This was made much worse with the October 12 “patch Tuesday” update, driving up the latency to 31.9 ns,” the report says.
According to a separate report from Wccftech, Microsoft could release a patch for the L3 cache latency issue on October 19. The CPPC issue could also be resolved with a driver update that may be released on October 21.
We’ll see what happens next week, but if you’ve been having the feeling that Windows 11 feels slower than Windows 10 on your AMD-based PC after upgrading, you may want to skip or uninstall the first “Patch Tuesday” update for the OS. As of this writing, Microsoft has yet to mention these performance issues on the release notes for yesterday’s Windows 11 KB5006674 patch.