why would it have to do with the source voltage of the outlet?
unless you have a really crappy psu it shouldnt make a real different on the rails the psu produces...
im rather guessing its the spd as well, lets hope just the spd blew or got corrupted for some reason.
there have been reports about corupted and damaged spd chips on tccd sticks on other boards as well and they stop working with certain timings.
i havent tested my memory in anothwr system tbh, maybe its not dead after all?