Hi. Look, lashton. If you would like to compare general performance check the "Sum of FPS Benchmarks", at the resolution you prefer. If you want to play a specific game, then check specific benchmarks. F. Sim X is the less representative of them all.
Just look, in F.Sim X, ATI 2900,4850,2600,4870,3850 ,etc.all of them around 23 or 25 fps. And also you´ll see your beloved 8800gt beating a gtx280. Ridiculous to use that benchmark as an evidence of any gpu's power.
Now, in general performance, a 4850 beats any 8800 at any resolution. Not to speak the 9600gt (wich is INFERIOR to a 8800gt, not the way around)