Microsoft released today an update for Windows 7 and 8.1 users, KB4073576 and KB4073578 designed to fix the unbootable state issue that some AMD devices ran into after installing the out-of-band security updates that Microsoft released last patchday.
An update is available to fix the following issue that occurs after you install January 3, 2018—KB4056897 (Security-only update) or January 4, 2018—KB4056894 (Monthly Rollup):
AMD devices fall into an unbootable state.
AMD users (especially on Athlon systems) began to report issues with the update shortly after Microsoft released it and Microsoft halted the delivery as a consequence.
About the given Information
Does it hurt when Intel/Microsoft would finally release more information? Nope, their articles and KB related information are mostly none existent or really none informative. These two patches are not documented and there are remaining questions, like do you need to install the old updates first and risk bricking your system before installing the updates? And which AMD systems are targeted by the patches?
Way too less information are given about the updates and what they change, together with the lack of information about the affected systems and what to do in case you are coming from a fresh Windows installation – so overall all you can do is install the updates and hope nothing gets bricked.