Ok this is a Der8aurer video, and for those of you who don't know who he is, he's well respected in the pc community. He did some tests to try to figure out the problem with the high temps on the 7900 series and came to the conclusion that it's most likely a faulty Vapor Chamber on the heatsink. You can search him up on youtube, idk if links are allowed in here. Search Der8baure, I am wrong-Amd is in big trouble.
It seems that AMD will either have to do a recall which is the right thing to do, or they will just do it by RMA and hope not to many ppl notice or care enough to do an RMA. AMD this is your time to do things right by the gaming community and just do a recall, if it is a vapor chamber problem!