Most people shouldn’t rush to install new versions of the operating system from day one, and Windows 11 is no exception to that rule. AMD has posted information on a couple of bugs that can reduce the performance of Ryzen processors running Windows 11 by up to 15 percent, although the amount of slowdown you see will vary depending on what you’re doing and what CPU you’re using. AMD expects both bugs to be fixed by the end of this month.
The first issue that AMD has identified increases the latency of the L3 cache by up to three times, affecting applications that rely on fast memory performance. AMD says that most affected applications will slow down by 3-5 percent, but some “commonly used esports games” could experience drops of 10-15 percent. AMD says that a Windows update will fix this problem later this month, so as long as you check for and install Windows updates regularly, you won’t have to do anything special to resolve the problem.
The second bug is related to an AMD processor function that tries to use the fastest individual CPU cores when running light-threaded tasks instead of treating all cores equally. AMD doesn’t put a number on this, but says the problem “may be more detectable” on processors with eight or more cores and a TDP of 65W or more. This would include most Ryzen 7 and Ryzen 9 2000, 3000, 4000 and 5000 series desktop CPUs and APUs. AMD says a “software update”, not a Windows update, will be released to fix the issue at end of October so you may need to install new AMD chipset drivers or some other software to fix it.
The AMD Ryzen issues are independent of the performance slowdown caused by some of the Windows virtualization-based security features. In particular, testing by outlets such as Tom’s Hardware has shown that the Memory Integrity security feature can reduce performance by a few percentage points in some games and general computing tasks, although results vary widely depending on the software you are using and the processor you have. The feature is included in both Windows 10 and Windows 11, but is disabled by default in both operating systems for all but the most recent laptops and desktops sold by major PC manufacturers.