I'm on my 2nd GA-X58A-UD3R (first one died - no life @ powerup after 6 months of flakey operation) - the current one and the one before both had problems booting if the mains power lead wasn't first removed to tunoff standby power for the motherboard. Even then there was a 1 in 10 chance it would fail to boot (no display output and a beep code) or random peripherals would not be present under windows (WinXP Pro / WinVista Ultimate x64 / Win7 Ultimate x64) as though the global HW reset to the hardware wasn't doing the right thing and some hardware blocks had hung.
Another problems is that restarts or shutdowns from WinXP Pro hang at the point the machine should remove the power / reset i.e. after the "Do not remove power saving settings" popup has cleared and just the blue screen and cursor are displayed. WinVista and Win7 can reboot and shutdown, but the subsequent restart can be problematic. Beep codes at POST, no display or on board peripheral not present in devise manager when you log on.
Tired several clean installs of varous the OSes, two different power supplies, and stripping the unit down to minimal hardware. motherbaord, i7 x980, memory, graphics card (GF GTX480), raid controller (Hightpoint RR3510) + Drives. Flakeyness regarding startup / shutdown persists. The system is rock solid once I can get it to boot correctly - that is until I want to reboot or shutdown.
It all looks like a poor motherboard design combined with crap bios sw not driving the power mangement and reset controller correctly. The latest two Bios updates haven't aided the situation either. And unfortuantely I can't revert to the one befor the FF bios... which appeared to be a little better... as its no longer available on the Gigabyte site :-(
Anyone having similar problems... or got any thoughts or suggestions?