AMD users can now download a patch that promises to fix a Windows 11 bug that can cause Ryzen chips to slow down.

On Thursday, AMD released a new chipset driver to address how Windows 11 can throw a wrench into the “UEFI CPPC2” system on applicable Ryzen processors. The system was created to help the OS determine which CPU cores to use for a high boost clock speed. However, AMD discovered a bug that’ll cause the UEFI CPPC2 to miss scheduling the best CPU core for a given programming task.

“Applications sensitive to the performance of one or a few CPU threads may exhibit reduced performance,” AMD warned earlier this month. Ryzen chips with more than eight CPUs cores and run with a TDP of over 65 watts are particularly affected, the company added.

In response, AMD’s latest chipset driver version 3.10.08.506 has been designed to “fully” restore the UEFI CPPC2 functionality in Windows 11 build 22000.189 or newer. The company published instructions on installing the new driver.

“AMD has verified that the behavior of UEFI CPPC2 ('preferred core') is working as intended on compatible AMD processors,” the company says. “AMD and Microsoft recommend that users promptly install this update on affected systems.”

However, Microsoft is still working on a patch for a second bug that can also drag down a Ryzen chip’s L3 cache latency performance when running Windows 11. If left unpatched, the bug can cause apps and games to run as much as 3-5% slower. For now, Microsoft has only released a test patch for Windows 11 Insider users on Build 22000.282. Mainstream users can expect the patch to roll out over the automatic Windows Update function.

PCMag