Try unplugging all of the components, like the hard drive and all that stuff. And do NOT do the towel trick again- it only is a temporary fix that does more damage than it does good.
Very nice PC, although you got ripped off massively. I don't like making people regret something good, but the same could have been built for around 900 pounds less. That case is awesome though.
Don't black holes come from stars many, many, many times the size of the sun when they go supernova? If so, how the hell would two protons colliding make a black hole?
AMD processors are fine, especially the 5000 series because they run cooler than the 6000 series. Intel just has the edge at the moment. Also, the 8500GT is massive fail for anything other than LFS, I would go for a 9500GT if I were you.
Building your own PC is like a lego set for lab rats. The only thing you need to do is have us help you pick the right parts, not handle the parts like a gorilla, and don't try to cut anything down.