GeForce GTX260+ vs Radeon 4850 Part 1: Performance

Direct3D (TrAA/AAA)

This set of benchmarks is designed to test nVidia’s transparency anti-aliasing (TrAA) and ATi’s adaptive anti-aliasing (AAA). This class of AA tackles objects called alpha (transparent) textures that are not affected by regular multi-sampling, textures like grass, chain-link fences, tree leaves, and similar. I used super-sampling on nVidia and quality on ATi respectively so both vendors were taking super samples, making it a legitimate comparison.

These titles are recycled from previous benchmarks and were picked because their benchmarks cover areas with significant alpha content, usually open areas with vegetation. I also picked them because I could get both vendors to reliably apply TrAA/AAA. In some titles like Call of Duty 4 for example, the 4850 didn’t seem to enable the feature.

Because the titles are a mix of new and legacy games, I used a mixture of resolutions to keep the framerate at reasonable levels in most situations.

OpenGL games were not tested because ATi’s AAA functions in OpenGL but nVidia’s TrAA does not.

Amazingly, after totally dominating thus-far, the 260+ appears to hit a wall. It posts an average loss of 10.49% to the 4850, getting beaten in five out of the nine tests, including getting utterly mauled in Serious Sam 2 when running 8xAA. Remember, the 260+ has almost twice the memory bandwidth and almost twice the memory size of the 4850 so whatever is causing this, it isn’t due to a lack of memory resources on the nVidia card. In some situations the 4850 seems to lose hardly any performance compared to the same benchmarks being run without AAA.

The issue of TrAA/AAA demands further investigation and will be covered in part two of this article, but for now I checked the titles where the 260+ was beaten badly (Call of Duty 2, Pacific Assault and Serious Sam 2), and screenshots indeed confirmed the 4850 was applying AAA.