As with Hard Reset, Dirt 3 prefers Nvidia GPUs. The GTX 670 averaged 72fps at 2560x1600, 5% slower than the GTX 680, 44% faster than the HD 7950 and GTX 580, and 16% quicker than the HD 7970.
The GTX 670 averaged 46fps when testing Just Cause 2 at 2560x1600, setting it 4% behind the GTX 680 and 2% lower than the HD 7970, as well as 15% ahead of the GTX 580 and 28% beyond the HD 7950.