Originally Posted by brunner
Why don't you try running SLI with the 1st and 3rd PCI-express slots? On my Gigabyte board, I'd only get 8X speed but it makes no difference in terms of performance. The only difference is that the boards would run cooler. I've only tried this with the 280GTXes but there's a good chance it would work with the 480gtxes. PCI-express speed is really not the bottleneck even when you're using multi gpus.
The problem is that its not even 8x, the 3rd PCIe slot is only 4x. That will definitely have an impact on performance. Plus it would be humping my power supply instead with the way this Antec 900 is set up.