The Crytek engine is just one of many, but Far Cry is a good game to tax the graphics card with textures, shading and lighting. We turned on the flashlight in our custom time demo, Cooler01, to make sure the cards got a thorough workout. Far Cry also has HDR (High Dynamic Range), which helps test the effects of HDR code in testing.
In Far Cry something oddly happened to the NVIDIA 6600 card when we overclocked. The scores actually decreased instead of increasing with the higher clock frequencies. Other than this anomaly, the pattern continued. Even with the odd performance hit, the order was GTO / XL in first, 6600 in second and the X1300 Pro in third.