Computer Stuck at Gigabyte Splash Screen

I share my computer with my father in order to pay off a debt I owe to him, and when I arrived home in the afternoon I was greeted by him, informing me that my computer wouldn't turn on. Generally this would simply be a random issue, or perhaps he turned off the computer and thought it was in sleep (though he's smart enough to tell the difference.). This time, however, was different.

I turned the computer on, and to my horror the splash screen shows and then the computer hangs. The only responsive key is Tab, which then shows me the detailed POST description. It tests my memory and shows my processor, etc as well as my drives, but after that it freezes at 'Looking for IDE drives...'. At that point, the only responsive (often it isn't responsive either) key is Delete, and that simply shows a 'prepare to enter Setup' message, and proceeds to do nothing else.

I have already tried draining my capacitors (turning my PSU off and holding down the power button), removing and replacing my CMOS battery, continually restarting it, pressing multiple buttons, removing and then putting back my GPU (had to in order to expose my battery) as well as disconnecting and then reconnecting my two drives. I've considered reseating my RAM, but in my past experience doing so has done nothing for previous, similar problems.

Both of us have done absolutely nothing that could have damaged the BIOS.

-Specifications-
GPU: NVIDIA GTX 260 Core 216
CPU: Intel Core 2 Extreme QX6850
RAM: 4GB DDR2 PC8500 Corsair Dominator
Motherboard: GA-EP45-UD3P
OS: Windows 7 Ultimate 64-bit