We found out that Intel chipsets can and do support SLI. Nvidia has enabled its cards to run on Intel chipset based motherboards, but only on the professional X5000 chipset combined with a Quadro 4600 or 5600.
Our sources had a chance to play with such a platform and two Quadro cards are able to make a preview or render in SLI mode.
We are not sure what happens when you plug two Quadro cards into a desktop motherboard, but there is a chance that this might work as well. The trouble is that Quadro cards costs two to three times more than the “normal” Geforce cards and the workstation or server motherboards that can take care of two Quadro cards are really expensive as well.
The second big downside is that Quadros aren't very good for gaming, but it can be done, you just have to pay a hefty amount of money and you are good to go.