OMG. I think I fixed it.
Ok so I noticed I lost some coolant from my reservoir on my ETF rig when I also noticed it was OFF. I pulled it apart last night and this morning. After looking it over it appeared that it leaked from a loose hose right on the CPU block (probably because I adjusted the frame's feet on Thursday and shook it around). I cleaned up the board but it still wouldn't act right. I suspected it leaked directly into the CPU socket, though it was hard to tell because it must have been a tiny amount of coolant and it must have evaporated quickly. The coolant I use is mostly distilled water, but it's most definitely conductive because of the metal additives I mixed. The titanium dioxide left a little white residue on the plastic socket cover where it dried. I knew I had to get that AM4 socket guard off so I could inspect and clean any residue. I've never been able to remove one of those without breaking it, but at this point I figured I already broke the mobo and maybe the CPU so what the hell might as well try. I watched a video or two on youtube where this little girl carefully takes a precision screwdriver to remove the plastic socket cover, and she made it look so easy. 5 minutes later I'm looking at plastic fragments of what used to be my socket cover but yes, there was some coolant stain on the metal socket connections. I cleaned them off with a fancy toothpick brush and some 91% isopropyl alcohol. I also cleaned the CPU pins. Next I took that CPU and what was left of the plastic pieces of socket cover and just kind of mashed it all together hoping for the best. I stuck the aluminum piece of a wraith stealth (I took all the fans off and use these for other stuff) on there, connected the power cables, keyboard and monitor, and jump started it with a screwdriver and bam into the BIOS we go. I dodged another bullet I think. I need to go ahead and assemble the rest of it, but while it's still mostly apart I'm going to clean my radiators really good.