Desktop PC. Gigabyte Motherboard, P4, 3.2ghz Built myself and worked fine for 6 months. Now I have a problem with powering-up. It powers-up for 1 sec then stops. This is enough to turn on the LED on the motherboard, spin all the fans etc. This 1 sec. power-up then is cyclical. It keeps on initiating a power-up every 5 secs. It did this a few times last week but after 3 or 4 attempts to power-up it then did power-up. Now it doesn't power-up, it just keeps on trying without success. I appreciate your help.