CoD 4xAA
Call of Duty 4xAA

Notes
With 4xAA enabled, we begin to see some real separation between the high-end, mainstream, and value cards in Call of Duty, even at the low resolutions. While the RADEON cards with 256-bit memory interfaces are able to push frame rates in excess of 100 fps at 1024x768, the greater demands of 4xAA are beginning to saturate the other cards. This is what makes these cards such great performers.
You will also see that the RADEON 9800 PRO 256MB outperforms its 128MB cousin by 29% at 1600x1200, this is the first time we've seen this in a game based on the Q3 engine. This is a big swing too, as the RADEON 9800 PRO 128MB isn't delivering playable frame rates at this resolution (although this is subjective) while at 80 fps, the RADEON 9800 PRO 256MB definitely is.
Those of you that ponied up the extra dough for this card will likely be glad to see this. In fact, your card is running neck-and-neck with the RADEON 9800 XT. If you were considering a 128MB RADEON 9800 XT card, you may want to think twice before you make your final decision.