I have the misfortune of being stuck with an AGP motherboard. I'm
don't feel the need to ditch my Athlon 64 3000+ just yet, but at the
same time I don't feel comfortable investing money into a dead
technology like AGP.

Most of the fancy new cards are PCI-Express only, and I can't really
use 'em unless I overhaul my entire system. So at this point... is the
7800GS worth my $300? Or would I be stupid to spend any money on a
dead technology?

I'm not very picky with my PC games. I'm perfectly content with
1280x768 resolution *without* AA, as long as all the other details are
close to maximum. I don't need to be playing at 120 fps all the time
either. I can tolerate an average framerate of 45-50 fps, but not any
lower.

With that in mind... how long will the 7800GS keep me content with the
latest games until it can no longer satisfy my requirements? 9 months?
18 months?