My system refused to boot after a restart, no post, beeps or fan power. I'm guessing that the problem is with either the MB or the PSU (Cooler Master GX-550W) after stripping most other components out, but have no idea how to tell which it is... my feeling is that I'll be returning the motherboard to Gigabyte, but if anyone could give me a good diagnostic to positively identify the culprit before I RMA it, that would be great :-)
