Benchmark Results: DiRT 3
DiRT 3 is the only game we’re testing with native AMD HD3D support; that means it works with Radeon cards without the TriDef driver. We highlight the HD3D results with red to separate them from the rest of the pack. Also, note that this game requires patch 3.3.12 from the folks at DDD in order to run the game in TriDef 3D mode.
This title is unique in that HD3D must be run in DirectX 11 mode, but the TriDef driver only works in DirectX 9 mode. Because it can handle it, we’re running 3D Vision in DirectX 11 mode also, and we set shadows, post processing, and ambient occlusion to their lowest settings in order to get the best visual result from Nvidia’s solution. As a result, native HD3D, TriDef, and 3D Vision all use different visual settings in this benchmark. Though certainly not ideal, it does facilitate an effective comparison between all three paths in a real-world environment.
Note the anomalies with the game’s native HD3D support: at 1280x720 the Radeon HD 6970 suffers terrible performance, which is remedied at 1920x1080. Conversely, the Radeon HD 6790 performs excellently at 720p and then fails at 1080p. The other solutions don't suffer from those performance aberrations.
Add anti-aliasing to the mix and the only real change is that the lower-tier graphics cards slow down. They remain viable, though. Native HD3D support continues to suffer from a strange resolution glitch depending on the Radeon card getting tested. This phenomenon is repeatable, even when cards are swapped out and graphics drivers re-installed.