New home-built AMD athlon iix4 620 system with Biostar a785g3 mobo and 4gb DDR3 ram. Computer runs fine when left on. But, if it ever gets shut down, will not boot. I get fans, lights and hard drive spins up, but no boot. The "cure" is to unplug the 20 pin cable and plug it back in. Then system boots normally after that and this has happened twice now. Is this the symptom of a flakey mobo or psu? Thanks for any help
Sorry, it is a 24-pin connector. The power supply is an Antec 380W, 80+ certified. Besides the motherboard and cpu, I only have 1 HDD and 1 optical drive. No PCI (or other) cards, so the PSU calculators I've looked at indicate 380 should be plenty, but I don't know.