Microsoft has released a cumulative update (KB5007215) for Windows 11 (opens in new tab), and with it, AMD can finally put the ropey performance at launch to bed. The fix for the L3 Cache problem has been resolved, and should now be rolling out to machines everywhere, along with security updates and patches for other Windows 11 problems.
AMD had previously released fixes for the problem, as we reported at the end of last month (opens in new tab), but these are now baked into the operating system itself. This should mean that a lot more AMD users have access to their chip's true performance, and won't need to apply any more updates from AMD or Microsoft.
There's a short video on Microsoft's support site (opens in new tab) that goes over what's in the patch, and the L3 cache problem that affects AMD's poor performance is the first up. There's not a lot of detail on offer here, simply that, "An L3 caching issue where some devices with AMD Ryzen processors experience application performance issues" and that it has now been resolved.
Another problem that has been resolved is an issue with the new Start and taskbar not working properly after upgrading from Windows 10.
This is a problem I've seen first hand. Despite my main PC running the Windows 11 insider preview without issue, on performing the upgrade to Windows 11, I couldn't use the Start menu at all and the Taskbar was dead too.
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I solved the problem by creating a new user account, which essentially performed a clean install, so it's good to see that Microsoft has resolved this for others.
Windows 11 should offer the update automatically unless you've paused updates for some reason—in which case now is a good time to do a manual check.
Microsoft does appear to be solving the launch problems quickly enough, but Windows 11 still isn't in a state where we'd recommend everyone upgrades to it just yet. For that, we'd recommend waiting until the first major update, which is expected in spring 2022.