Update: Intel too confirms Microsoft is right not to take the blame.
It has been a pretty eventful week for Microsoft and Intel in terms of major news and rumors. First up, we had the "Downfall" GDS vulnerability which affects almost all of Intel's slightly older CPUs. This was followed by a leaked Intel document which suggests upcoming Wi-Fi 7 may only be limited to Windows 11, Windows 12, and newer.
Meanwhile, users of the two latest generations of Intel CPUs were affected by a Windows update issue where the system crashes with a blue screen of death (BSOD) displaying a "UNSUPPORTED_PROCESSOR" error, even though it is supposed to work perfectly. (Microsoft recently updated its support list for both Intel and AMD.)
MSI, which seems to be the most commonly affected motherboard vendor out of all, published a workaround yesterday which you can find here. The problem is mainly affecting Intel's Z690 and Z790 boards, which are chipsets accompanying 12th and 13th Gen Alder Lake and Raptor Lake parts respectively.
Microsoft has also updated its health dashboard page today with new information and details about the issue. Interestingly, the company says that its latest non-security preview updates, ie, Windows 11 (KB5029351) and Windows 10 (KB5029331), which seemingly triggered this Unsupported CPU BSOD error, is not really what's to blame for the error. It says that this is an issue with a "specific subset of processors":
After investigating these reports, we have found that the “UNSUPPORTED_PROCESSOR” error was not caused by issues in KB5029351 and is limited to a specific subset of processors. We are collaborating with device manufacturers (OEMs) and will temporarily mitigate this issue by not offering KB5029351 to Windows devices that might be affected by this issue. If you still experience this issue, please contact your device’s processor manufacturer.
If you are one of those affected, you can still provide feedback to Microsoft The company's guidance on how to properly give feedback on the issue can be found in this article. You should also contact your motherboard maker and CPU maker, which seems to be Intel at the moment.