Installing Windows 11 on a PC the checker says is unsupported

You can. With TPM 2.0 already there it's just the CPU check, and Microsoft's own registry bypass covers that: regedit > HKEY_LOCAL_MACHINE\SYSTEM\Setup\MoSetup, add a DWORD AllowUpgradesWithUnsupportedTPMOrCPU = 1. Then download the Windows 11 ISO, double click to mount it and run setup.exe from inside Windows. It keeps your files and apps. Updates: Microsoft says unsupported PCs aren't entitled to them. In practice the monthly updates have kept installing on machines like yours, but the yearly version upgrades may need the same trick again. You'll also get a 'system requirements not met' note in Settings. Back up first either way.