Along with the increased CPu clocking, Dell's system comes complete with Nvidia's Quad-SLI system, which incorporates two dual-GPU GeForce 7800 GTX 512MB cards, resulting in a total of four GPUs running in SLI mode, and a total of 2Gb of memory.
The two SLI PCBs are connected together with a special connector to work under the master and daughter concept.
However, you would expect Nvidia to show off a quad-SLI configuration with four normal GPUs connected to four different PCIe slots. This would give us a clearer picture of the FSAA capabilities of the Quad-SLI. The Dell/Nvidia demo could be considered and treated as a Trade Show feature, since even Nvidia's partners could not support it with their products, due to its high development costs.
Dell's XPS 600 Renegade system should be available in spring.