One thing that differentiates NVIDIA chipsets from other motherboard chipsets today is the ability to run two video cards in conjunction to increase gaming performance. No other motherboard chipset has this capability at the moment (with ATI's Crossfire coming soon but not available yet).
Setting up SLI is easy and pain free. After inserting two 6800GTs in the two PCI Express x16 slots, and making sure the SLI card is in SLI Mode on the slot, power on the computer and install the Forceware drivers. After enabling SLI in the drivers you have SLI on your cards and increased performance over a single card.
SLI is available on the 6600, 6600GT, 6800, 6800GT, 6800 Ultra and 7800GTX cards. Unfortunately, despite several hours of work, I wasn't able to get two 7800GTXs in SLI mode. GIGABYTE includes two SLI cards with their GA-8N-SLI Royal, one for regular NVIDIA video cards and another for their 3D1 cards. 3D1 has two 6600GTs or 6800GT GPUs on the same card. The 3D1 cards only work on motherboards GIGABYTE manufacture and only on specified boards. The GA-8N-SLI is one of the supported boards.
