Interesting. I know that if you do not update your SLI Profile to version 7 only one card will work. Both of my cards are just about almost equally being used, SLI bar graphs are showing balanced usage, and temps are almost the same, perhaps off by 3-5 degrees. Also I had to "Add" the game's .exe file to the Nvidia Control panel's 3D Settings.
How many FPS are you getting? At what resolution?
60 frames capped because the system selected Vsync after I selected no. Wierd. So through out the whole SP game it would just stay at 60 frames on Extreme @ 1650 rez. I will try toggling that setting again to see what in reality my max frames are.