The State of DirectX 11 - Image Quality & Performance
Dirt 2: Performance & Verdict
Like Aliens vs Predator, Dirt 2 has relatively demanding recommended system requirements, although not quite at the levels that Bad Company 2 recommends. According to Codemasters, the game is best run on at least a mid-range Core 2 or equivalent Athlon X2 processor. Two gigabytes of memory and 11GB of hard drive space is typical. At least on paper, the game has similar graphical demands as Aliens vs Predator, asking for a NVIDIA GeForce 8800 series or ATI Radeon X1950 series card.
The primary features that DirectX 11 users will be getting are tessellation, screen-space ambient occlusion and Dx11 exclusive post-processing. However, anti-aliasing is available to all DirectX rendering paths. We chose to test the game with anti-aliasing set to 4x for both Dx11 and Dx9. All other settings were set to their highest available levels.
Dirt 2 features a built-in benchmark function hidden at the bottom of the graphics menu. This option is unavailable unless you create and log into a campaign account. It's one of the better built-in benchmarks we've seen in a game since it replicates the real-world gaming experience very well and therefore generates results in-line with real-world gaming performance. The benchmark itself is basically a short race on a track from the game. This isn't your typical scripted benchmark however, since all cars are AI controlled. It seems like they simply took a typical race from the game, ejected the player and replaced him/her with AI. You get to watch the action during the benchmark from the perspective of your AI replacement from the game's standard game camera.
Overall Dirt 2's built-in benchmark produces consistent results that are a good representation of real-world game performance. We used it for our performance tests. All of the results below are the average frame rates produced by the game's built-in benchmark. Each tested setting was benchmarked 5 times and the results were averaged.
There is an unmistakable performance delta between DirectX 9 and 11, although it is much smaller than the delta seen with some of the other games. This time around, the performance difference has nothing to do with anti-aliasing since it is available and enabled for both rendering paths. The game's use of tessellation, ambient occlusion and DirectX level-specific post processing effects are to account for the performance drop in Dx11.
Despite having relatively high recommended system requirements, Dirt 2 performed very well at all tested settings. While the 20-30 FPS delta is hardly negligible, the game's overall performance remains good across our tested resolutions and on both video cards. With every image quality setting pushed up to maximum levels, the Radeon 5770 had no trouble cranking out a respectable and very playable 40 frames per second (average).
Dirt 2 Dx11 Verdict: This is one of the games where you will definitely want to enable DirectX 11 rendering features when available. The performance drop hardly impacts gameplay and the game is smooth even with mid-range cards. While you may be able to salvage some extra frames per second with DirectX 9, it's not worth the image quality drop and you probably won't notice the extra performance in-game except with budget graphics chips.