Benchmark Results: Far Cry 2
At 2560x1600 with no anti-aliasing or anisotropic filtering enabled, the Radeon HD 4890 gives you exactly 10% more performance than the HD 4870 1 GB. At 1920x1200 and 1680x1050, the platform itself seems to be more of a limiting factor and performance differs very little between the various mid-range cards. In sharp contrast to Crysis, Ubisoft's Far Cry 2 is easily playable at the highest resolutions.
Turn on the eye candy and all of the cards take a much more noticeable performance hit—even the flagship Radeon HD 4870 X2. The Radeon HD 4890’s advantage over the single-GPU 4870 1 GB remains fairly modest—it certainly doesn’t make the difference between enabling a resolution that wouldn’t have been available before. Moreover, it remains just slightly faster than Nvidia’s GeForce GTX 260 Core 216. It’s an improvement, but we’re still not compelled to spend an extra $75 bucks on it.