Update for you all. So, I picked up the RX vega 64 liquid-cooled. Plugged her in and couldn't get any video output. None of the ports outputted anything, couldn't even get into the bios or anything. The computer booted up fine, but no video.
So somehow I figured out how to get the Vega FE working, turns out I just needed to unplug one of my pci cards and it booted up fine! OOB Not sure why that made it work, maybe someone can fill me in? It will give me that weird black screen if I have all the pci slots used.
Anyone need a used Vega 64?