Alrighty, so I'm currently running my desktop in Safe Mode, transferring all of my important graphics files, songs and other stuff to my portable hard drive. And I'm going to wipe the drive, and re-install Windows. Luckily, since it's a Dell XPS 630 they supplied me with all the discs for every driver on the machine, and a reinstall disc for Vista Ultimate.
If, after all of this, it still doesn't work. Then I know it's the card. And I'll have a squeaky clean HDD to boot! ... heh.