AMD Begins Rolling Out ZEN 5 Processor Performance Patch Today, Fixing Performance Drop When Not Using Administrator Account

Previously, some users testing the performance of AMD's ZEN 5 architecture processors discovered that using the system's built-in but by default disabled Administrator account could enhance the AMD processor's performance. This means that under normal circumstances, using a standard account actually results in a performance decline.

At that time, AMD responded by pointing the finger at Microsoft, attributing the issue to Windows NT's permission control problems that prevented AMD CPUs from achieving optimal performance. AMD stated that this issue only affected the ZEN 5 architecture, but tests found that the ZEN 4 architecture was similarly affected.

Starting today, AMD is rolling out a performance patch to Windows 11 Insider Preview users. After testing, this patch will be pushed to the official version of Windows 11, being delivered directly through Windows Update.

So, what caused the performance drop?

AMD explains that under the current state of Windows 11 24H2 version (i.e., using a regular administrator account), the system fails to correctly utilize the branch prediction feature of the ZEN 5 architecture, which is the fundamental reason for the performance decline.

Branch prediction in CPUs helps minimize performance loss, and modern CPUs use branch prediction to enhance performance. Without it, performance would significantly decline. It's not that AMD's ZEN 5 processors are unable to use branch prediction; they just weren't leveraging it fully.

As for how AMD resolved the issue, it's unclear. In previous statements, AMD mentioned that the problem was related to Windows NT's permission control, suggesting that AMD and Microsoft may have collaborated to find a solution.

The performance patch is currently being distributed through the Windows 11 Release Preview Channel, under the build number 26100+. If you're using the Windows Insider Release Preview Channel and an AMD ZEN 5 CPU, you might see the update in Windows Update.

Finally, AMD provided tests for the performance patch:

For example, with the AMD RYZEN 9950X, after fixing the issue, the performance (in terms of game FPS) in "Far Cry 6" could increase by up to 13%, while "Cyberpunk 2077" and UL Procyon Office (an office productivity benchmark test) performance could increase by 7% and 6%, respectively.

Additional Note: In this new announcement, AMD did not mention the ZEN 4 architecture, although previous tests showed that the ZEN 4 architecture was affected by the same issue. It's unclear if AMD has conducted further tests independently.