Lutris has a script for GZDoom, I played a few months ago.

They outperform the RX 7800 XT, but frame generation is exclusive to the RX 7000 series and it’s likely to make a bigger difference down the road.

RX 7800 XT

Finally, it’s a must have update for AMD users. I hope it doesn’t take long to appear on Flathub.

You are probably better off running emulators, anything from Atari to Sega Genesis and SNES should work fine.

As other people mentioned, the PSU is too weak for the hardware.

You didn’t mentioned with distro you are using, with your setup you are supposed to use a bleeding edge distro, like Arch, Fedora or openSUSE Tumbleweed. Distros like Ubuntu doesn’t have up-to-date drivers for your hardware.

Audio crackling could be caused by Pipewire, reverting to Pulse Audio would probably fix the issue.