Bioshock (DirectX 10)
An impressive FPS-based game with a great story, Bioshock impresses with both graphics and its ability to drag you along in the gameplay. It has both DX9 and DX10 render paths and should make a great benchmark for graphics cards promising the best of both worlds.
At both the 1600×1200 and 1920×1200 resolutions, the move from a two GPU to four GPU solution didn’t result in a very noticeable performance gain. In fact, the four-way solution was actually a bit slower from the extra software overhead involved in the driver. However at the 2560×1600 resolution, the CrossFireX performance gains are beginning to show. Adding in HD 3870 to your HD 3870 X2 setup gets you a 30% overall gain in frame rate and adding a fourth GPU gets you another 10% or so. Going from a single 3870 X2 card to a pair of them nets a 41% performance increase.