Windows 11 update is affecting AMD-based PCs performance

• Windows 11 update KB5006674 has performance issues with AMD processors.
• Microsoft and AMD are working to fix the problems.
• The issues could cause a performance impact of up to 15 percent or more.

Shortly after Windows 11 became available for eligible devices, AMD revealed that many of its processors (including Ryzen chips) have a compatibility issue that can translate on up to 15 percent of impacted performance. Now, during the October 2021 Patch Tuesday, Microsoft has released the first quality update for the new version, and it appears it is making the problem worse.

According to a report from TechPowerUp, after installing the update KB5006674, Windows 11 seems to experience higher latency, negatively affecting performance a lot more, even though it’s unclear how much worse.

During the initial rollout of the new OS, Microsoft and AMD discovered at least two issues. The first one is an L3 processor cache latency problem, which according to AMD, could cause up to 5 percent of performance impact on certain applications and up to 15 percent on games. And the second one is an issue with the preferred core (UEFI CPPC2) feature built-in to the AMD processors, which is a feature that can change threads to the more capable cores as needed. AMD says this could be a noticeable problem on devices with a processor with more than eight cores.

Both companies are aware are actively working on a resolution, which is expected to arrive by the end of October.

If you have an AMD-based system, it’s recommended not to rush the upgrade and stay on Windows 10 as long as you can, or at least until the problems are resolved.

If you have already upgraded to Windows 11 and are noticing performance issues with the computer, you can always roll back to the previous version with these instructions.