Well, things have been pretty steady for now. I got the latest drivers, installed them all properly, and I've boosted the fan speed on the GPU to 100% without overclocking the GPU itself. Everything works fine EXCEPT when it gets to 60`+ Celcius. That seems to be the cutoff point for artifacting. I've only been getting the BSOD when nTune craps out on me (nTune is a program provided by nVidia for overclocking and testing hardware.) But RivaTuner works fine. No crashes or anything; I just can't adjust settings on the motherboard with RivaTuner like I can with nTune.
Anyway, this is pretty depressing, because I know with my old 7800GT (I accidentally RMA'ed it when the Motherboard was the real problem) was capable of a lot more. I'm not really sure what to do at this point; I really doubt that the BIOS is the problem, though I suppose I could try flashing it if nothing else works. Could there be any other reason behind this? Someone suggested reseating the card in the slot. I was a little taken back by that comment, because I'm pretty damn sure I know how to install a component...