Doom 3 is typically dominated by Nvidia as its core design was matched for this game. However, ATI has taken the title with single core designs and lower overhead drivers.
This is where we encounter the first of some CPU limitations as the low resolution and image quality settings bottleneck around 126 frames per second. The ATI card can produce higher frames per second under the current system configuration. The reason is the driver. ATI has been producing drivers with less CPU overhead associated with their design. This means that the CPU is utilized less and can output more performance for the graphics subsystem.
The winner overall is clearly the new 8800 series cards. Looking at the results at all resolutions, the new DX10 cards push past the Radeon X1950XTX from 1280x1024 and up.