Benchmarks: Far Cry 3, Hitman
Far Cry 3 shows the full benefits of multi-GPU technology as GTX 660 Tis offered 35% more performance than the GTX 680 and HD 7970, and the HD 7850s gave 13% more frames than both single-GPU solutions.
The GTX 660 Ti in SLI were less effective at 5760x1080, landing just 15% ahead of the GTX 680. Similarly, the HD 7850s were only 5% faster than the HD 7970.
Hitman: Absolution favors AMD GPUs, so it wasn't too surprising to see the HD 7850s outperform the GTX 680 by 31% and the GTX 660 Tis by 5%, while the pricey SLI setup could only match the HD 7970.
At 5760x1600, the Crossfire cards only averaged 19fps, but that was still ahead of every other test configuration.