Quad SLI: GeForce 7900 GX2

Call of Duty 2:

Publisher: Activision

We used the full version of Call of Duty 2, patched to version 1.2. The game makes use of some awesome effects and is generally very graphically intense and immersive. That's helped by the tremendous smoke effect that Infinity Ward have created - it's better than anything we've ever seen before. There are also real time shadows and a subtle HDR lighting effect too.

The gameplay is not as linear as the first version of Call of Duty, and Infinity Ward has ditched the rather old Quake 3 engine in favour of creating its own proprietry graphics engine to render the effects. There is something about the game that makes it very intense and you often find yourself having to take a break from the action because you're too overwhelmed by its immersiveness and intensity.

We used a four minute portion of the first level in The Battle of El Alamein, starting the clock from the beginning of the battle, completing the missions in the same order, stopping the frame rate recording when we had played four minutes of the level. We ran this three times to check that our results were consistent.

The Optimise for SLI option was enabled, as it provides a frame rate boost for all video cards - all other options were set to their maximum values. Finally, we tested the cards at three resolutions with varying anti-aliasing settings to compare the cards in an apples to apples format.

Another thing that we haven't touched on thus far is the performance of Quad SLI at lower resolutions. 1600x1200 is a comparatively low resolution and the GeForce 7900 GX2 Quad SLI configuration fell behind by over 40% in Call of Duty 2 at 1600x1200 4xAA 8xAF.


At 1920x1200 4xAA 8xAF, the 7900 GX2 Quad SLI system was 35% slower.


Finally, at 2560x1600 2xAA 8xAF, the GeForce 7900 GX2 Quad SLI cards were 30% slower than the BFG Tech GeForce 7900 GTX OC SLI configuration.

This didn't seem right because Call of Duty 2 supports SLI out of the box, so we queried NVIDIA's driver team about the problem. They said that they'd not seen this kind of performance internally, but there appears to be an issue where Quad SLI appears to fall back to dual-GPU mode in certain applications when running at 4xAA/8xAF, resulting in lower performance from the 7900 GX2's slower-clocked GPUs. The driver team has been investigating this problem, but there is no ETA on when a fix will arrive. We tested the cards at the recommended SLI8xAA 8xAF at 2560x1600 only to experience nothing more than a slide show.

Whatever the case, we were able to attain consistently poor results in Call of Duty 2 on the GeForce 7900 GX2 Quad SLI configuration. If you're a Call of Duty 2 junkie and want to play at the highest resolution and detail settings, stick with GeForce 7900 GTX SLI or Radeon X1900 CrossFire for now.