The Windows 11 update released earlier this week may have actually made the problem worse, but at least a fix is imminent.
The L3 latency bug is one of a pair of problems that AMD identified with Windows 11 earlier this month.The other Windows 11 problem AMD identified, which can prevent high-core-count, high-wattage Ryzen chips from correctly assigning work to the processor's fastest individual cores, will be fixed via an AMD driver update.
A post shared on Reddit suggests that the Windows update is being targeted for release on Tuesday, October 19th, while the AMD driver update for the other problem should be released two days later, on the 21st.