Microsoft has acknowledged a gaming performance reduction issue reported by Windows 10 users after installation of the update KB5000842 or later. The company is also rolling out a fix for this issue that plagues Windows 10 versions 2004 and 20H2 using the “Known Issue Rollback”.

Here are the details. Microsoft notes that it might take up to 24 hours for the resolution to become available to affected Windows 10 consumer devices. It also recommends restarting the device for faster application of the resolution.

A small subset of users have reported lower than expected performance in games after installing KB5000842 or later updates. Most users affected by this issue are running games full screen or borderless windowed modes and using two or more monitors.
Affected platforms:
  • Client: Windows 10, version 20H2; Windows 10, version 2004
  • Server: Windows Server, version 20H2; Windows Server, version 2004
Resolution: This issue is resolved using Known Issue Rollback (KIR). Please note that it might take up to 24 hours for the resolution to propagate automatically to consumer devices and non-managed business devices. Restarting your device might help the resolution apply to your device faster. For enterprise-managed devices that have installed an affected update and encountered this issue, it can be resolved by installing and configuring a special Group PolicyNote Devices need to be restarted after configuring the special Group Policy. For help, please see How to use Group Policy to deploy a Known Issue Rollback. For general information on using Group Policies, see Group Policy Overview.