I'm a poor person to give an opinion on this as I'm a Mac guy...but if you're on the third power supply, that would seem to point to a problem to me. I'd consider switching it out for a fresh one and the possibility of keeping a spare on hand for just such an emergency...

Best

AA

ps: ...even my tech head brother has joked about using liquid Nitrogen to cool his rompin' stompin' overheated computer.