The latest Windows 11 update is causing blue screens of death with a stop code of “unsupported processor” on some MSI motherboard-based PC systems. Microsoft has acknowledged the issue, noted the Verge, and stopped pushing KB5029351 updates to systems which would be adversely affected. MSI has yet to respond.
We have a pretty good idea about why some MSI motherboards are affected by this Microsoft OS update thanks to the experience of Tom Warren of The Verge and various redditors who have posted about their issues.
The “unsupported processor” BSOD only seems to appear on systems with MSI boards that have applied the latest BIOS updates. These BIOS files have been released for MSI Z690 and Z790 motherboards, in preparation for the arrival of Intel’s upcoming 14th Gen Core ‘Raptor Lake-S Refresh’ processors. They explicitly support “next-gen CPUs,” and appear to have caught Microsoft newest OS off guard.
Microsoft’s Windows 11 notoriously excludes what should be capable processors (like first gen Ryzen CPUs) from its compatibility list. Users of such systems have to fiddle with bypass techniques to get Microsoft’s latest OS to play nicely on their otherwise competent machines. It could well be the case that MSI’s BIOS tweak extending CPU support has triggered something in Microsoft’s CPU exclusion code.
“We are presently investigating to determine if this is an issue caused by Microsoft,” reads an update on the Windows Help Center. “We will provide an update when more information is available.”
So, what should MSI Z690 and Z790 motherboard users do now? If you haven’t already installed the Windows KB5029351 update, then put it off. If it is already installed and you get this BSOD, reports suggest that it is possible to recover Windows and rollback the patch. Coming at the problem from a different angle, you could avoid or roll-back the MSI BIOS update.
PC users with other motherboard brands might be wise to wait and see how MSI users get over this issue before seeking out similar 14th Gen Core CPU BIOS updates.
