I have a couple of boxes with different mobos. In one I have a Celeron 1.7 on a Gigabyte VIA PT800 board. I tried to upgrade to a P4 2.4 1MB, but no matter what I did, it wouldn' t post. No video at all. I tried three different boards, but no go. Now I tried a new Celeron D320. Same problem. I pulled the battery on the board to reset CMOS, but no good. PLEASE HELP with any suggestions at all....