Recently I've had quite a few people asking me how to solve problems with Quad SLI micro-stuttering so its still obviously an issue for some.
Therefore I have decided to put together this little guide for people which shows how I managed to resolve the problem:
Firstly download and install the newer Nvidia 179.83 drivers pack including the PhysX drivers (remeber to uninstall any previous Ageia physx software first).
once installed:
make sure that "geforce physx" is selected in the Physx options
make sure that quad sli is enabled.
reboot your system.
then make sure your 3d settings are as follows:
up to & inc. 16x anistropic filtering
up to & inc. 16x antialasing (
NOT 16Q - Quality antialasing)
under antialiasing select
override any application setting
You may also enable transparency up to & inc. supersampling.
Then under SLI mode select EITHER "Nvidia recommended" OR "3 GPU alternate frame rendering" (I personally recommend the "3 GPU alternate frame rendering" option, especially if you are going to enable geforce PhysX)
reboot your system.
Now finally, before you play any games,
in your actual game or application video settings select/activate the lowest or a low antialiasing setting, e.g 2x or 4 x antialasing (I wouldn't recommend going higher than 4x though I have sometimes activated up to 8x antialiasing in some games - still with override selected in the Nvidia control panel).
save your settings & reboot you system.
That's it. You should now be able to play with ultra high & ultra smooth framerates. Congratulations on all that money well spent.
n.b: this worked for me so i'm just trying to help. If this doesn't work for you then i'm sorry and good luck finding a solution.
Solve Quad SLI micro-stuttering 
