It’s different on the d3_c17 levels as the scene recorded on the d3_c17_12 map contains a street fight where the CPU has to process a lot of physics and AI for numerous game objects. You can see that in the diagrams: there’s practically no difference between the participants in 1024x768. In the highest resolution ATI’s cards have a negligible advantage of about 2-3 frames per second.
ATI’s cards look better when full-screen anti-aliasing and anisotropic filtering are in use. The architectures from the Canadian company are well suited for hard operational modes where there’s a high load on the graphics memory subsystem.
The SLI technology can’t show its best, as the speed of the central processor is the main frame rate limiter here. Anyway, you can notice a performance gain in high resolutions of the “eye candy” mode.