I've been having a power issue with my GA-MA770-UD3 over the last few months. This is how it presents: whenever the PC goes to sleep or is powered off, it won't turn on again. I can mash the power button, but there's absolutely no life - no fans spin up, no lights come on, nothing. The only solution that I've found so far is to physically unplug the ATX power connector and plug it back in again. After that, it powers up just fine.
At first, this was an intermittent issue, but recently its become constant. I've changed every BIOS setting I can, I've endlessly fiddled with the power settings within Windows, I've checked, double checked and triple checked that everything is plugged in and seated properly (going so far as to completely dismantle the entire system and reassembling twice) and I've tested with a spare PSU - and the issue persists. At this stage I'm convinced that its a physical defect on the board, but I was hoping someone could shed some light on the issue before I pursue an RMA.
System specs:
AMD Phenom II x4 955 BE (stock clocks)
GA-MA770-UD3
4GB DDR2 800MHz Kingston RAM (4X1GB)
Seagate Barracuda 320GB 5,400RPM
Palit GTX 460 768MB (stock clocks)
Color 650 Watt PSU
Windows 7 Ultimate Edition (64bit)