I have made a few diagrams based on ComputerBase.de review to compare GTX285, HD5870 and GTX480 graphics cards.

Test setup
CPU: Intel Core i7 965 Extreme Edition (overclocked via multiplier to 3.87 GHz quad-core)
Motherboard: Asus Rampage 2 Extreme (Intel X58, BIOS-Version: 1639)
Hard Disk: Western Digital Caviar Black 1TB, 32 MB cache
Memory: 3x 2.048 MB Corsair DDR3-1600 (8-8-8-24)
OS: Windows 7 Ultimate 64
PSU Coolermaster M850 Real Power Pro Modular (850 Watt)
URL http://www.computerbase.de/artikel/h...itt_testsystem
Nvidia Drivers: Nvidia GeForce 195.62
GTX 400 Drivers: Nvidia GeForce 197.17
ATI Drivers: ATi Catalyst 9.11 (Dirt-2-Hotfix)
HD5870 ATi Catalyst 10.3a Preview
HD5830 ATi Catalyst 8.703_RC2
HD5670 ATi Catalyst 8.69 RC3

The diagrams are based on average FPS with optimal - in game - settings for different combinations of screen resolution, AA and AF.
The charts have the same size and max scale at 120FPS. This way, the diagrams are comparable, but on the other hand, the 1920x1200 1xAA, 1XAF chart misses the World in Conflict SA 150,3FPS FPS value.