2560x1600 - Gaming Performance
Increasing the resolution to 2560x1600 hammered the performance of Nvidia-based graphics cards, giving an edge to AMD Radeon boards. The Radeon HD 6970, for example, moved into third position matching the performance of the GeForce GTX 570.
Only the GeForce GTX 580 managed to average 60fps at this extreme resolution, while the GTX 570 dropped to 52fps and the Radeon HD 6970 rendered 51fps. While these cards all provided playable performance, others like the Radeon HD 5850, HD 6870 and GeForce GTX 470 started to struggle averaging scores in the low 40's.
Below them on the graph, many cards dipped down into the mid 20's. Although the game still looks relatively smooth at 30fps, we found that the mouse movement felt very off, somewhat delayed if you will.