Switching things from Call of Duty, here our 9800 GT appears to perform quite well while our 4770 suffers and our 4850 is on top for a moment. It appears with UT3 prefers stream processors in numbers until you get to such a high resolution that memory bandwidth kicks in.

Left4Dead is Valve's latest game and very popular as with everything they put out. Here we see the 4770 lag behind the 4850 until we hit 2560x1600 where the GDDR5 memory shows it's benefit. The 9800 GT OC and 9600 GT remain slower.

3DMark is synthetic benchmark so I wouldn't put much into it but here's some potential of these graphics cards.