collective: ATI Super AA vs. NVIDIA SLI Anti-Aliasing

Radeon X1800 XT 4xAA

GeForce 7800 GTX 512MB 4xAA

You wanted to see more benchmarks and screenshots of the two setups running in action. Well we’ve delivered, as we re-ran our benchmarks with both the super-hard-to-find GeForce 7800 GTX 512MB and the GeForce 7800 GTX 256MB, as well as the Radeon X1800 XT 512MB. ATI and NVIDIA’s latest driver sets are used as well.

CrossFire’s key advantage over NVIDIA SLI is ATI’s Super AA performance advantage with the Radeon X1800 XT over the GeForce 7800 GTX cards. ATI’s redesigned compositing engine brings a massive boost to Super AA performance, resulting in little or no performance hit for 8xAA at lower resolutions. In a graphically-intensive game like F.E.A.R for instance, at 1280x960, performance is nearly cut in half for the GeForce 7800 GTX 512MB SLI setup, from 93 fps to just 42. Meanwhile, the X1800 XT CrossFire is cranking along at 51 fps, a drop of just 16%, or 10 fps! Gamers looking for the best combination of image quality and performance though should definitely consider ATI’s CrossFire solution.

Even 14xAA is quite playable at resolutions as high as 1280x1024 in some games. You can’t really say this for the GeForce 7800 GTX 512MB with 16xAA. Until CrossFire’s infrastructure catches up to SLI, we have a feeling that ATI’s CrossFire technology will continue to play second fiddle to NVIDIA SLI despite ATI’s superior performance in higher AA modes.

ATI’s CrossFire implementation isn’t as elegant as NVIDIA SLI. In the case of X1800 CrossFire, you have to mess with thick dongles to connect both graphics cards to each other, while only ATI’s flagship X1800 XT has a corresponding CrossFire master board to pair it with. This leaves ATI X1800 XL users out in the cold unless they want to pay $100+ more for a X1800 XT CrossFire card that will be running with half its memory disabled. With NVIDIA you can mix and match cards as long as they’re based on the same GPU: you don’t need to pair the GeForce 7800 GT for example to a more expensive master card to get SLI to work.