Far Cry 2
We tested Far Cry 2 using the game's built-in benchmarking tool, which allowed us to test the different cards at multiple resolutions in a precisely repeatable manner. We used the benchmark tool's "Very high" quality presets with the DirectX 10 renderer and 4X multisampled antialiasing.

This is one game that will punish even the latest video cards at relatively common resolutions—and we weren't even using the "Ultra high" quality settings. Notice how, just at 1680x1050, the Radeon HD 4870 with 512MB of memory is slower than the 4870 1GB. That effect is magnified as the resolution increases, and the 512MB cards become completely useless at 2560x1600—even the relatively powerful configs, like dual Radeon HD 4870 512MB cards in CrossFire.

As for the two cards we're ostensibly reviewing, well, the GTX 285 is indeed the fastest single-GPU solution, and two of them in SLI are faster than anything else we tested. Yet a single GTX 285 turns out to be slower than the (less expensive) Radeon HD 4850 X2, so the ol' value proposition looks shaky. Meanwhile, the GTX 295 nearly averages 60 FPS at 2560x1600, easily ahead of the 4870 X2 but only a tad faster than two 4870 1GB cards in CrossFire.