Far Cry
The Far Cry test is the same one used on high-end cards, so it's an absolute measure. Once again, the 400/800-clocked XFX card produces decent framerates at 1280x1024 with in-game settings dialed up to very high (no HDR, however).
2x FSAA and 4x AF add too much of a burden on these cards, and anything above 1024x768 could be considered choppy. From a pure performance perspective, the GeForce 6600 DDR has the measure of ATI's RADEON X1300 Pro thus far, eclipsing it in every gaming test.