Running around the beginning of the Enpro map is quite dark, even for Doom 3 but there is quite a bit of action and lots of flashy effects used. All of this is displayed very nicely on the HIS X800GT. Frames never drop below 30 which the 6600GT does on more than one occasion. The actual experience of playing is very similar to that of the 6600GT, but when you are in a heavy fight, the HIS X800GT handles things just that bit better, although not enough to increase the settings to that of the X800XL which almost runs happily at this resolution with 4xAA and 8xAF. Since the game is rather dark, AntiAliasing doesn't have much of an impact on the visual quality, but should you wish to run some AntiAliasing with Doom 3 and the HIS X800GT, you will need to drop down to 1024x768.

At this resolution, with 4xAA and 4xAF, things are still in favour of the HIS X800GT over the 6600GT. Also don't forget that these numbers are taken with the card at ATI defaults, and that the HIS iTurbo software will overclock this card for you (more on this and its performance impact later).

I have to say that I do prefer the image quality on the HIS X800GT to the NVIDIA 6600GT, simply because you get a softer image with the HIS X800GT. Since Doom 3 is a dark game, the emphasis on jagged edges is less noticeable but there are occasions when you will notice them and while the HIS X800GT won’t remove them or hide them, it can dull them somewhat.