Hello everyone I was hoping someone could help me with my dilemma. I have an Asus P5NSLI with a Pentium D + 8GB Wintec DDR2 667 Ithat I had dropped in to replace my very limited Gigabyte Mobo that came with my pc.. I had run the Asus board for about 8 months and then one day the computer had locked up while trying to boot and after a rest it would not post. I ended up trying the usual tests such as resetting the CMOS which did help for one more boot and then it would not post again. I decided to go back to the original board which I still had put away because I figured that the motherboard was fried and after hooking everything up that board would not post either! My immediate thought was that my CPU was dead. So I had ordered the Q6600 which I was already planning on upgrading to and today I decide to give another shot at the asus board since neither board posted last time. I dropped the Q6600 into the asus board with the 8GB DDR2 and, again - no post. I am kind of running out of ideas on what it could be because I tried switching ram and that did not help, i switched video cards, and nothing. Any ideas on what it could be that would be causing the boards not to post? Any ideas welcome! Thank you all for your help.