AMD warns of up to 15% Windows 11 performance decrease

AMD says it observed performance hits of up to 15% on Windows 11-compatible AMD processors when using some applications.

"AMD and Microsoft have determined that compatible AMD processors may exhibit reduced performance in certain applications when running Windows 11," the multinational semiconductor company said in a support article.

Microsoft and AMD are investigating two separate issues affecting AMD CPUs' performance on Windows 11.

Updates to fix the issues expected later this month

One of the compatibility issues with AMD processors leads to increased measured and functional L3 cache latency, which may impact the access time to the memory subsystem for some applications.

The expected performance impact in affected apps is between 3 to 5%, but this performance hit could reach 10-15% for eSports games.

AMD CPUs are also being hit by an unexpected slow down on Windows 11 caused by UEFI CPPC2 (preferred core) not scheduling threads on the processor's fastest core.

This performance decrease is most noticeable on apps sensitive to the performance of one or a few CPU threads and is more detectable in CPUs with more than 8-cores above 65W TDP. 

Microsoft and AMD are working on updates to address the performance issues, with an estimated release time later this month.

Redmond has not yet acknowledged these issues and is yet to update the Windows 11 health dashboard to include them.

Customers advised to stay on Windows 10

As a workaround, AMD recommends its customers to continue using a supported Windows 10 version until Microsoft delivers an update addressing these performance issues for all impacted systems.

"AMD and Microsoft are actively investigating these known issues for resolution via software updates," AMD said.

"In the interim, customers using compatible AMD processors affected by these issues may continue to use a supported version of Windows 10."

Microsoft has released Windows 11 worldwide this week and is now rolling it out to new Windows 10 devices and those pre-loaded with Windows 11 via Windows Update.

AMD also published a press release on Windows 11's release day, saying that over 175 AMD CPUs are now compatible with Windows 11.

However, the company did mention the performance issues impacting compatible AMD CPUs on Windows 11, including the latest released Ryzen CPUs.

"AMD Ryzen processors are supporting the new Windows 11 operating system experience, delivering the integration and performance needed to take advantage of exceptionally fast speed, responsiveness and efficiency," AMD said.

Besides issues with AMD CPUs, Microsoft has also revealed Windows 11 compatibility problems with Oracle VirtualBox and Intel "Killer" networking software, as well as with Dell's SmartByte networking tool.