Hey guys,
I've got a radeon 9700 as well, and it wasn't working when I first installed the card. Then I changed the AGP aperture down to 64 megs from 128, still nothing - but then I changed it down to 32 megs. That did it, for some reason, and now it runs, and looks great! (That sounds like an ad for some sort of fitness product '...and now I look great!' sorry, couldn't help myself)
Uh, execept for the occasional texture popping, but hey otherwise, it's amazing!