hhmm, that doesnt seems possible either, unless you were using your CPU as ashtray, as P-4 comes with thermal Diode, even the P-3 was in with that. as when it gets hotter, it shuts down the system. though strange problem you're telling that a P-4 has black marks on it. then this is one in a million case I have ever seen for P-4's
Intel Core2Quad 2.66Ghz 12MB L2-Cache
4096MB DDR Kingston Hyper-X
XFX 9600GT AlphaDog
Seagate 2 X 320GB SATA2
LG L246WH Flatron 24"