The New 4000 Series of cards from ATI are now great with AA and AF.
They outperform most of Nvidia's in AA and AF.
I believe there is a Review online where they test this, and the new ATI cards preform great. I have a 4870 and I have tested it on a video benchmarking and stress testing program( http://freestone-group.com/video-car...k-results.html
) Not the best Benchmark though as it uses mostly shaders, and Nvidia cards have faster shaders than ATI, so their for biased.
I went to the CCC control center for the card, and set the AA on 2X, I got 340-390 FPS. Put it on 4X I got 320-370 FPS. On 8X I got 290-330 FPS.
With the CCC you can also change the filter type to "Wide-Tent" which allows for AA sampling up to 16X!
I applied that and I received 165-180 FPS. Now this is with a fully Overclocked 4870, which is capped at 790Mhz core and 1100Mhz memory (4400Mhz Effective). Most cards are able to hit this mark as well.
But remember, AA is only good if you not playing at a native resolution, if you are, all you need is 2X or 4X. I play Age of Conan at 2X and get VERY stable FPS (30-70), and at 4X it drops a mere 5FPS.
The new ATI cards are very good at handling AA so if you wish to invest in one, I would highly suggest a HD 4870. If you wait, you could get the 1GB model or even the HD4870X2. I have heard nothing but greatness from this card so it might be worth the wait.