Well, Thor is proving to be more stubborn than I thought. Apparently it's unhappy having all its PCI slots plus it's AGP slot used. Something about "IRQs" or something.
So, Thor's going back in the closet. [Brady] might be right about the box though; I'm afraid it might be ending it's lifetime; I found two bad sticks of ram out of four, which makes me thing it's the motherboard and not the ram. Might be time to part that out (along with all the other computer stuff I need to sell) and rebuild.
So, now we're thinking (where we = me) that it'd be easier to build either a micro-atx computer, or buy an XBox and mod it. Considering I'm not really looking for the PVR functionality, only the PVD functionality, the XBox route would work; although it wouldn't be as satisfying, and not that much cheaper, either. Sigh. Stupid computers.