Looks like two 12v (yellow) wires burned somehow. Computer was running fine last night, and for the past few months on end. Went to boot up this morning, and it was a no go. Investigating, I found what you can see in the pics above. (sorry for the blur. It's in a dark corner and my camera struggles with closeups in any condition)
So, what is the prime suspect, PSU or mobo? (I've yet to dig out my other PSU to try)