Windows 11 update: degrades AMD Ryzen CPU performance by up to 15%

Windows 11 is now officially here and right after Microsoft's new operating system launched, an update was pushed out that reduced AMD Ryzen CPU gaming performance by up to 15% on some systems.

Microsoft is working on a fix for the Windows 11 update, that will boost performance back up on AMD Ryzen processors. The company notes there's an issue with high L3 cache latency, which reduces gaming performance by up to 15% depending on the AMD Ryzen CPU being used.

In some testing, the folks at TechPowerUp found that the L3 cache latency that normally is at 10ns is at a much higher 31.9ns in the new Windows 11 update on the AMD Ryzen 7 2700X processor. Before the update, the latency was at 17ns... quite the increase.

AMD has chimed in saying that the patch for this issue will arrive on October 21 for the preferred cores bug, while the L3 cache latency issues on Windows 11 will be fixed in an update on October 19. Not long to wait, but how do these issues get through both AMD and Microsoft is beyond me.