On latest hotfix drivers (16.4.2,16.5.1,16.5.2) I'm noticed that all DX12 apps exit to desktop so I debugged one of apps an noticed this:

(8b8.294): Illegal instruction - code c000001d (first chance)

(8b8.294): Illegal instruction - code c000001d (!!! second chance !!!)

*** WARNING: Unable to verify checksum for C:\WINDOWS\SYSTEM32\amdxc64.dll

*** ERROR: Symbol file could not be found. Defaulted to export symbols for C:\WINDOWS\SYSTEM32\amdxc64.dll -

amdxc64!OpenAdapter12+0x15e0e:

00007ffd`a2776f0e f30fb8436c popcnt eax,dword ptr [rbx+6Ch] ds:00000000`1cc002fc=00000001

Instruction popcnt is SSE 4.2 instruction, so my question is: DX12 is supported on non-SSE 4.2 CPU or not ? I think NVIDIA drivers works fine on non-SSE 4.2 CPUs