For tat price, atm, you've only got two choices, as far as I know, 9800 Pro or GeoForce FX5900.
They run pretty much neck and neck, I've owned both, and the 9800 Pro beats the 5900 in 3D Mark 2004.
But in real everyday usage terms, I found it hard to tell the difference.
Although both do look a little different. I run CoD & UT 2004 in 1600 x 1200 with most eye candy turned on, the 9800 definitely looks better to me, but that is a personal preference thing.
I'm actually selling the FX5900 shortly, I've scrapped one machine, I really don't need it, have a few pieces to sell. Quite a few parts went to machines I've just built for people, but I still have some parts left.