Ahh the black screen of death!
Out of curiosity, when was the last time you checked the inside of your system for dust build up?
The processors heat sink is the first place you want to check.
Came back to edit in a link, try this program for monitoring your temps and voltages:http://www.cpuid.com/hwmonitor.php
Edited by MrBruce1959, 04 April 2010 - 05:40 AM.