have an older Dell server box. Running Win 7. Box had completely white screen. Rebooted, came up fine and then after 5 minutes went back to white screen. Thought 4870 video card went bad. Pulled card, cleaned dust bunnies and re-installed. Nothing comes up on screen at all, not even bios. Checked PSU, checks out. Checked connections, fine. Put card in another machine. Checks out fine. Checked KVM switch. Fine. Put older PCI card in, no joy. Monitor fine. Lights on board light, fans buzz. Hd running, CD-ROM running. Tested power to board and card, fine. Board has onboard speaker, no beeps? Even though it's an older box, can't leave a puzzle alone. Any clues to this riddle? I'm guessing the board, but not sure.