There is an option to "turn on visual indicators" for sli to see how the cards are balancing the load and I have only ever seen it kick in on games.
On my nVidia control panel I have the option to create a graphics profile for any . exe file which includes things like selecting alternate frame rendering or split frame rendering. Some games run better depending on the settings.
Also as far as I know SLI (at the time I made my system) is the only way to do flashy things like x16 anti-aliasing.
Likely SLI comes into play in 3d studio or CAD type programs but it doesn't seem to have any effect on things like photo shop.
EDIT: Link to nVidia SLI forums. I was just checking through here and it appears that gaming is pretty much the only reason people have them. And that some users like to build what they perceive as the beefiest machine possible.
I am running 2 nVidia geforce 7600 gt cards on an asus P5ND2-SLI board. My choice was based on price more then performance. And the upgrade-ability. I can swap my 2 cards out for something better when it becomes more affordable and then but another of the same cards later down the road when they are cheaper to run in SLI again.
Edited by - conquistador on 10/13/2007 4:30:31 PM
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