In an update to a Windows 11 support document as spotted by Neowin, Microsoft warns that a watermark will be added to the desktop on any PC that's been upgraded to Windows 11 without meeting the minimum requirements. Further, a notification may pop up in the Settings app to indicate that the computer doesn't meet the necessary requirements.

Microsoft issued a warning for users who install Windows 11 on unsupported devices. You won't receive any updates!

Microsoft warns users of unsupported hardware using Windows 11 with a disclaimer Windows 11 will add a watermark if system requirements aren't met Continuing to use Windows 11 on incompatible hardware may void support and warranty.