Yea the mb needs to support SLI...goto nvidia and read up and google about SLI....it has to be setup properly or it won't work....I bought a computer with it from pcclub.com....and read up some on the whole thing...I think I just googled about SLI before I bought so not sure exactly where I read,I just read all over and went with it....it played DOOM 3 on it's ultra High setting that they did not recemond setting it to...the whole game thru flawlessly....and the expansion pack.
...just got Oblivion for Christmas and set it to highest setting and so far so good.