NVIDIA
Quad SLI was probably the most debated topic of Cebit. You have to buy two special video cards which come with two 7900 GPUs on some kind of dual video card.
Each card takes up one PCI-E x16 slot and two power connectors. The clock speeds with 500 MHz core and 600 MHz memory are somewhere in between the 7900 GTX and 7900 GT. Every GPU uses 512 MB memory which brings the total setup to 2 GB of video memory.
According to NVIDIA, system builders are already building and shipping Quad-SLI systems.
When someone asked about the power consumption of such a monster system at the press conference, the NVIDIA spokesperson said: "oh we're quite happy with it, only 680W [PSUs are powering our demo systems]."