I’ve got Ryzen 5 3500X very cheaply (like $20 for both CPU and board), because it - I quote “doesn’t run Windows, just Linux”. It’s a six-core/six-thread CPU originally targeted to asian lower-end OEM market, having SMT turned off permanently and it’s the only Ryzen 5 3xxx missing in Windows 11 supported AMD processors. Indeed, both Windows 10 and Windows 11 installers ended in B.S.O.D. around 20% from the start. But when installed elsewhere, Windows 10 worked without any error, so I started tinkering in EFI setup… Long story short: There is an option in EFI called “SMT”. It has two possible states: Disabled and Auto. When set to Auto, Windows fail to install, when set to Disabled, both Windows 10 and 11 work. It seems that both systems simply presume the CPU has SMT and fail when trying to use it. When SMT is disabled in EFI, this does’t happen and even Windows 11 recognize the CPU as supported and install from the original ISO without any modifications. Mystery solved.