AMD confirmed that there is a major bug in upgrading Windows 11: CPU speed drops by up to 15%, and a patch will be released soon

The much-anticipated Windows 11 was officially launched on October 5th, but many bugs were revealed afterwards. Just now, AMD confirmed that after upgrading Windows 11, it will cause AMD Ryzen game performance to drop by 15%. Currently, AMD and Microsoft have stated that they will issue a patch to resolve the BUg.

According to AMD, when used with the Windows 11 operating system, it may cause the performance of all its Windows 11 compatible processors to decrease in certain applications. For example, in e-sports games, the extreme outlier of performance degradation is as high as 10-15%; for applications, AMD claims that its performance impact is also as high as 3–5%.

AMD stated that the bug will affect every AMD Ryzen CPU supported by Windows 11. In other words, all Zen+, Zen 2 and Zen 3 CPUs, including Ryzen 2000, Ryzen 3000, Ryzen 4000 and Ryzen 5000 processors, will be affected.

In addition, AMD EPYC (Xiaolong) and some newer Athlon (Athlon) chips selected by the company's data center will also be affected.

(You can see the full list of affected CPUs here. AMD says that every AMD chip in its list of best gaming CPUs is included:
https://docs.microsoft.com/en-us/windows-hardware/design/minimum/supported/windows-11-supported-amd-processors?ranMID=24542&ranEAID=kXQk6*ivFEQ&ranSiteID=kXQk6.ivFEQ-.iZIwsDA.sjl4UW1rlQWVg&epi=kXQk6.ivFEQ-.iZIwsDA.sjl4UW1rlQWVg&irgwc=1&OCID=AID2200057_aff_7593_1243925&tduid=%28ir__o9eqgapktgkf6xz9sap6wurx6u2xr6csnyiol2kn00%29%287593%29%281243925%29%28kXQk6.ivFEQ-.iZIwsDA.sjl4UW1rlQWVg%29%28%29&irclickid=_o9eqgapktgkf6xz9sap6wurx6u2xr6csnyiol2kn00

According to AMD consultants, the problem can be attributed to two types:

First, the measured and functional L3 cache latency can be increased by approximately 3 times, which means you can see the impact of measurement utilities, which can cause actual performance degradation of games and applications. This BUg affects applications that are sensitive to the latency of the memory subsystem, resulting in a 3–5% performance degradation. This problem also leads to 10-15% performance degradation abnormal values in games "usually used in e-sports", which is not surprising, because games are very sensitive to memory and cache latency.

In addition, AMD's "Preferred Core" feature directs single-threaded applications to the two fastest cores on the chip, and may not work as expected. This will mainly affect the performance of light-threaded applications. AMD stated that this performance degradation may be more pronounced in chips with 8 or more cores and a TDP rated power of 65W or higher.

Although AMD stated that there is no more information to share with respect to the above issues, in a latest announcement, AMD stated that it is actively investigating these known issues with Microsoft and will resolve them through software updates. Update when its announcement becomes available.

AMD recommends that customers experiencing problems can "continue to use a supported version of Windows 10", which seems to mean that it is unwise to upgrade Windows 11 before the problem is resolved.

AMD said that it is expected that Windows Update will solve the L3 cache problem, and the software update will also solve the problem of UEFI CPPC2's preferred core technology. Both may be realized this month.

The following are the results of the test conducted by foreign media on this issue:

• The latency of the tested and normal L3 cache may increase by about 3 times.
• Applications that are sensitive to the access time of the memory subsystem may be affected.
• The expected performance impact of the affected applications is 3-5%, and there may be 10-15% outliers in common e-sports games.
• UEFI CPPC2 ("Preferred Core") may not prioritize scheduling threads on the processor's fastest core.
• Applications that are sensitive to the performance of one or a few CPU threads may exhibit performance degradation.
• In 8-core processors with greater than 65W TDP, the performance impact may be easier to detect.

It is reported that Microsoft has officially launched Windows 11 on October 5th. The new system will bring users a more concise appearance, and will carry out touch experience, voice input, collaborative editing, application development, accessibility enhancements, and games. With a brand new upgrade, eligible Windows 10 PCs can be upgraded for free.