I am a 73 year old guy who has an ASUS CM5570 desktop with an Intel Core 2 Quad Q8200 processor. When switched on it would seemingly try to start, then shut off & restart, but with a black screen. A system disc in the optical drive does nothing. The fans continue to run and the LEDs for the optical drive and the hard drive blink for a few moments. I can't get a BIOS screen by holding F8. A friend who usually can figure things out told me to remove memory sticks and replace them one at a time. No difference. Then he told me to unplug the drives and reconnect them one at a time. No difference. His best guess was a power supply, which I have now replaced but it also made no difference. I bought a POST tester from Cyberguys that plugs into a PCI strip and I get two codes: 0P and 03. Unfortunately, the codes are keyed to various BIOS and I have no idea what BIOS ASUS uses. Even if I did 0P is not even on the list and the defects listed for 03 are not in my vocabulary. Aside from replacing the motherboard and processor, what are my options? Any ideas out there?
Looking around on the Internet I found a site which has experts familiar with ASUS products who will help diagnose for a fee. It cost me $38 and I was in a chat for over an hour with a guy who seemed very knowledgeable and was extremely helpful. It looks like the motherboard is at fault and I have ordered a replacement. I have a 30 day satisfaction guarantee on the service. I will post again after I install the motherboard.