1. The DFI lanparty range.
2. Wait a while for the new cores, from the specs, the X900 will be the top card, but we will have to wait to be certain. For your question though, the 6800ultra is better, but it is wasting money, when the 6800gt is able to get to ultra speeds and beyond easily.
Cisco CCNA, Comptia A+, 1/3 through CCNP