Here follows a change of subject...
The x1800xt 512mb is in the same price bracket as the 7800gtx 256mb, and consistently outperforms it. It is better at running simultaneous HDR and antialiasing, and its A 512MB CARD for God's sake!
I got a GeForce 6 card last time, but this time I'm going with ATI because they have actually pushed things forward a bit in terms of HDR capability. GeForce have basically just popped another 8 pipelines on a 6800ultra and branded it a new series. Granted, in terms of raw power the 512mb gtx is the best card going, but it's certainly too expensive.
I don't think the press have appropriately gotten onto the fact that only the X1800XT properly supports HDR. In the last GPU war, the x800 was faster, but the 6800gt was unanimously agreed to be the better card for it's SM3 support. As soon as more HDR games come out, the x1800xt is gonna get alot more respect.
EDIT: Maybe go with the 256mb GTX if you plan on doing SLI, but personaly I'm NOT because it's so noisy, hot, and power consuming.
EDIT EDIT: I SERIOUSLY wouldn't consider a x800gto2 if you have more money. It doesn't even support SM3, let alone HDR. It will struggle with the likes of COD2 and FEAR, and will DIE with future games like Elderscrolls: Oblivion and Unreal tourniment 2007.