ATI Radeon HD 5770 Issues

Last Thursday I logged onto my computer and saw that my drivers needed updating. I updated them, and mid-way, the screen went black. I know this is usual, but I left the computer shortly after. I came back a half-hour later and the screen was still black, so I reset the computer, it didn't help.

WHAT I'VE TRIED

Resetting the CMOS
Using the built in graphics card in the motherboard to update drivers
Reseating the graphics card
Unplugging all hardware except the monitor

SPECS

Desktop w/ Windows 7 64-bit
MSI 880GM-E43 Mother Board
ATI Radeon HD 5770 GPU
AMD Phenom II X4 Quad-core Processor

What I think I should try is to put it in another computer to see if it would give that a display, or put another GPU in my PCI-E Slot to make sure it isn't burnt out. I'm trying to reset the BIOS on it to see if that would help, but I can't figure out how.

So, what I'm asking is for you to help me diagnose what is wrong, tell me how to go about resetting the GPU's BIOS, and tell me whether trying any of the things I listed above is pointless or not. Any help whatsoever would be greatly appreciated.

Edit: As it turns out, I had my monitor plugged into the on-board motherboard graphics, which worked before things started going bad, but not after, obviously. The on-board graphics worked when the GPU was out of the slot, but not when it was in.