Microsoft's Spectre and Meltdown update is breaking AMD PCs

Though the discovery of the CPU vulnerabilities known as Spectre and Meltdown have the worst implications for Intel users, AMD users aren't exactly out of the woods. Meltdown may not affect AMD processors, but Spectre does, prompting Microsoft to push out an update that patches those vulnerabilities. In a perfect world, that would be the end of it – at least until new exploits related to Spectre and Meltdown are discovered – but of course, we don't live in a perfect world.

As it turns out, that update (known as KB4056892) to patch Spectre vulnerabilities is breaking some AMD PCs entirely. Ever since Microsoft delivered the update last week, AMD users have been posting to the Windows support site with stories of PCs that refuse to boot. That, as you can probably guess, is not a good development.

Taking a quick glance at the thread of user complaints, this seems to be affecting older AMD processors, but there doesn't appear to be any official confirmation of that being the case. Microsoft, for its part, has acknowledged the problem in a new article on its support site. In that support document, Microsoft blames flaws with AMD's documentation for the problem.

"Microsoft has reports of customers with some AMD devices getting into an unbootable state after installing recent Windows operating system security updates," Microsoft writes. "After investigating, Microsoft has determined that some AMD chipsets do not conform to the documentation previously provided to Microsoft to develop the Windows operating system mitigations to protect against the chipset vulnerabilities known as Spectre and Meltdown."

For now, Microsoft has stopped the distribution of this update to PCs with AMD processors. We don't have a timeline for when a new update will be available, but the two companies are working together on a solution. We'll just have to sit tight for the time being, but if you have the misfortune of being the owner of a freshly unbootable AMD PC, you can find troubleshooting tips for Windows 10, Windows 8.1, and Windows 7 in the support document quoted above.