Mixed Nvidia and ATI GPU Performance

We mixed and matched Nvidia and ATI cards, with the Nvidia graphics card inserted into the primary display slot, as instructed by MSI. We have included the performance of single cards in respect to the combinations of cards we've used to show any performance advantage.


Addendum: MSI informed us on the day of publication that Batman was previously supported in mixed manufacturer mode under 1.3x drivers, but that support was removed with 1.4x in favour of mixed-ATI mode instead. However, during testing we were unaware of this and the Hydra logo and software still claimed it was supported.




Previously MSI told us to always put the Nvidia card in the first PCI-E slot and ATI card in the second, which we adhered to, however rather late through out testing we were also told that swapping these over sometimes gave a better result. We tried it and this is represented in the (reverse slot) result for the GTX 275 and HD 4770.

In Batman, there's clearly no benefit to the Hydra, with the single cards providing the smoothest framerate. We noticed that there was a flickering issue with some of the dynamic textures (cell forcefields for example) that only occurred in the mixed-GPU setups as well. Clearly the Hydra is doing something though, since the GTX 260 and HD 4890 combo is considerably faster than the GTX 275 and HD 4770 - it's not just taking the primary slot performance. This is further shown by the reverse slot setup too, which does see faster average frame rates but a lower minimum.

Again, Fallout 3 benefits the ATI cards with a smoother gameplay. A situation we've always known this to be the case outside of this in our normal graphics benchmarking. The single cards still do well, and we think the HD 5870 is doing most of the work when paired with the GTX 260, however those two cards together are worth some £300 more than the HD 5770 alone, and the 5770 is 40 per cent faster.

What can we say about Call of Duty 4 - more microstuttering and an overall suffocated performance by all accounts. Team Fortress 2 changes things up a bit though; here the HD 5770 is slower than the mix of GTX 275 and HD 4770, and GTX 260 and HD 4890, however if we look at it in more detail the addition of a HD 4770 appears to do nothing, and the overall power of the GTX 260 and HD 4890 should be far faster than these two as well. In addition, the reverse slot approach suffocates the performance as well.