lightlune

Just go with intel, low TDP and with an iGPU. For your use cases, i don't think you'll even care for performance hits (as long as you got decent amount of cores) because quicksync is so easy and you don't have to worry about gpu's until you get into gaming VM's. Plus (in my country at least) amd prices are bloated and stock is scarce.

Let me know how it goes, cause either way there's still a fair bit of work to be done to make it run near bare-metal and stable (although nothing too complicated). I highly recommend spaceinvaders unraid videos on youtube. My VM as it is right now wouldn't be here if it wasn't for his guides.

Create a new VM with the same settings, but set "Machine:" to "Q35*latest version*". There's a couple more tweaks you need and can do here and there, but Q35 should at least get your machine to boot normally (i think, if not, then we can start going through XML edits to make it actually work)

I've only managed to get one vm working with ryzen (for lack of cpu cores and gpu), so can't comment on any super specific gotchas with hardware. Probably would recommend getting an rtx card with usb c, so each guest gets it's own set of IO (you'll have to get usb c hubs though). Hopefully your monitors have a headphone jack (or you can get usb c adapters with a headphone port). CPU, if you wanna use plex, intel. if just purely gaming, amd with the highest amount of cores you can afford (8 core minimum in your case for dual core vms, 12 recommended for tri core vms). SSD, i have an nvme drive that i use exclusively for my vm's os drive (passthrough the nvme controller). I think that's the critical component that has made my vm feel bare metal. Plus, i can boot it like its any old bootable drive without unraid, if i need to. In your case, maybe sata ssd's would be better since the gpu's are already using a good chunk of pcie lanes. those are the things i can think off, top of my head.

Odd, i have the exact board as you (bios updated to 4.50) and i have no problems with booting windows 10 with a 5700xt (although there's still the reset bug). Only changes i made was an rcu_call flag in syslinux and disabled c-states in bios to stop the random system crashes when i deal with vm stuff. Care to share your XML?