Windows 11 went live this week after a little over three months of public testing with Windows Insider. The operating system booted with some known issues, but may have slipped undetected. AMD has confirmed that the processor has been adversely affected by the Windows 11 upgrade, resulting in poor performance in certain situations. Thankfully, the resolution is already underway.
AMD points out two distinct issues with the processor and Windows 11. The first is related to the L3 cache latency of the processor, which can be up to 3 times higher on Windows 11. This specifically affects the performance of apps such as: It may depend on access time to memory subsystems, such as fast-paced esports titles. According to AMD, performance can be as high as 15% in very specialized games, but performance impacts typically range from 3% to 5%.
AMD says it will probably be fixed in a patch update next Tuesday as a Windows 11 update later this month. This is the first cumulative update since the general availability of Windows 11, so many bug fixes should be published in parallel.
Another issue is that the UEFI system’s “priority core” feature does not schedule the fastest core tasks available in a particular scenario. This can affect the performance of applications that rely primarily on a single or a few cores, as multithreaded tasks use all available cores anyway. As a result, performance impacts can be greater for processors with a large number of cores and threads, especially those with 65W TDP and above. AMD does not explicitly state how big the impact on performance will be.
Anyway, a fix for this issue is also in progress. According to AMD, it arrives by “software update” instead of Windows Update, so it may be available in the form of a new driver release for Windows 11. This fix is also planned for this month.
This shouldn’t be a big deal, as Windows 11 is gradually being rolled out and many users are likely not yet upgraded. It’s not unprecedented that problems occur after these major new updates, at least the fixes are relatively quick. We also heard about the issue that virtualization-based security can impact game performance. This is currently being investigated by Microsoft. If you haven’t read it yet, read the Windows 11 review to see why we recommend upgrading to anyone using Windows 10.