I know I keep bumping this but haven't really been getting any responses from anyone.
Happened again today, same thing. The little pixelated square that you can see in the WoW video. This time it was in CSGO. I reset the GPU back to stock clocks and bumped up the voltage when I had my last post. Since my last post, today was the first time I had the issue. I bumped up the voltage some more and ran Valley for a few minutes and my temperatures never broke 63, so I'm good in that department.
I'm really concerned my GPU is very slowly dying. I got it used from a miner (only in use for a few months though I think). And it looked brand new when I pulled it out. I've used it on the GHz Edition clock speeds and the default clock speeds and haven't really seen much difference in terms of my issue. I was also getting that issue seen in the GTA IV video a few times in WoW and other games but that seems to have either become less common or disappeared since I'm back on 13.X patch. I'm inclined to think that was a driver issue as a few others on Reddit mentioned the same problem.
Does anybody have any suggestions about what could be going on? Am I looking at a dying card or am I just having really crappy luck with drivers. Again, this issue is so spread out and impossible to recreate willingly. It just happens very occasionally. See the WoW video above to know what I'm talking about.