I think the problem is in the power supply. (Keyword: I think. To be extremely, extremely honest, I'm mostly a software guy and don't know much about electronics otherwise... and definitely not power supplies) I opened up the power supply (well, sorta, I can only get the top partially off because the connector on the bottom is stuck in place) to clean it out and I noticed some caps had a sort of white goop (yeah, lack of a better word. Sue me.) around their bases or splattered on the sides. I'm not sure if that counts as anything; it might just be some sort of glue... but anyway there's also another thing, in a little plastic container that looks a little like a vertical version of a Mac's PRAM battery holder. It's round like a cap but I can't tell what it is. It's covered in a shiny yellow-red-black dried-up goop. I have no idea if it is something normal, but I did google around for pictures of inside a power supply and didn't see anything like it.

I can supply pictures if needed. But, I might just be being an idiot since I know nothing about power supplies... in which case, I apologize in advance for my stupidity.