Good effort!
The system powers off when the power button is held because of a BIOS settings. The options are "Soft Power Off" (which has a 4sec delay) or "Instant Off" which shuts the PC off immediately when the button id depressed. Can't be modified unless you can enter BIOS.
I think we've exhausted what can be done over the internet
A friend of mine found this guide
Method #1:
1. Shut your PC down (if you're reading this guide, than your PC isn't working anyways)
2. Hold the power button until the PC starts and shuts down again
3. Press the power button again, your backup BIOS should kick in now and should re-flash the main BIOS if there's anything wrong with it.
Method #2:
1. Shut your PC down
2. Hold the power AND the reset button for about 10 sec, than release.
3. Backup BIOS should kick in anytime soon now.
Method #3:
Had to use this one in order to get my 990FXA-D3 working again. Backup BIOS kicked in using method #2, but I was back to the good ol' no signal state once the procedure finished..
1. Short out pins 1 and 6 on the main BIOS chip (pin #1 should be marked with a red dot or whatever)
2. Tell a friend (or a relative) of yours to press the power on button
3. Remove the ghetto-like jumper you're holding between pins 1 and 6 as soon as you hear a beep.
4. Backup BIOS should kick in again and everything will (hopefully) be fine.
Uhm yeah, that's about it, I guess.
P.S Please bare in mind that the 3rd method should only be used if you have the following options:
Option #1 Follow my dumb advices.
Option #2 RMA the board.
I followed Method 1 and 2 but it didn't work. I tried method 3 but I have no paper clips only earrings which are tricky to work with...
*** Also I forgot to mention, when I run my PC without the Windows 7 CD, it goes straight to black screen with mouse cursor in it, but if I have win 7 CD in it loads up the GIGABYTE thing and then it goes to black screen with mouse cursor...