well i found the info in a place i probably should looked first. i used the geforce.com website tool to show how to set up a surround with accessory using dvi. looks like there is a option via triple 660 ti. it says 660 but 660 ti the lowest 3way config i think. i think anything 660 ti and up could use these configs. i took a snapshot of the 4 options for 4 monitors so thought i would share here.
GeForce GTX 670 Suround Vision.PNG (195.42 KiB) Viewed 5318 times
2) Power consumption (read as you NEED a monster PSU)
3) 2 way SLI (normal) is dependant on the nV driver team. 3 way is even more dependant on them. You may be better off with a 690, or a pair of 670's...
If you consider running 3 cards after considering the 3 above, go with it
i SO miss the +1 Button here in this Forum! QFT What Gilly said! Trisli is nice, if it works! driver for Games are just about 3-8weeks after a game release! at best!