R9 380 Monteray Black Screen after Apple Logo (works fine on Big Sur, did work on 1st boot on Monteray)

I had a working installation of Big Sur using MSI Armor2X R9 380 2GB GPU, GPU was working out of the box (without H.264 encoding/decoding but with HWAcceleration -radcodec or other boot-flags did not help me but that's a different story).

I did reinstall OS to Monteray (fresh install, not an upgrade) using same config and EFI and it... WORKED. I did use OS couple of hours, all went good. Made couple of benchmarks, GPU performance was ok. (still no HW H.264 decoding/encoding)

Sad story begins after the 1st reboot. I see an apple logo with loading indicator, and around halfway the screen goes black with color artifacts sometimes happening but eventually it goes just black. I did research that R9 380 is still supported in Monteray and using AMD8000.kexts which is still present in Monteray.

What did I try: all soft of boot-args found in Dortania guide, exactly:

1. agdpmod=vit9696 leads to same behaviour
2. agdpmod=pikera leads to same behaviour
3. Spoofing as R9 380X boots after couple of minutes of black screen but without HW acceleration
4. Spoofing as R9 390X boots after couple of minutes of black screen butwithout HW acceleration
5. Did try several SMBIOS, including: iMacPro1,1, MacPro7,1, MacPro6,1

My current boot-args are -v keepsyms=1 npci=0x2000 -rad24 nothing fancy, I did try removing -rad24, same behaviour, other boot-args are needed to boot

​