Modded drivers are needed as nVidia removed SLI support for cards with different amounts of memory.
Try the 310.70 drivers
Didnt work :(
My cards are:-
MSi N560GTX-Ti Twin Frozr II/OC 1GB
MSi N560GTX-Ti Twin Frozr II 2GD5/OC 2GB
Back to 310.
The previous version didnt work with my 2 x 560 ti (1gb / 1.5gb vram)
I'll give these a bash tomorrow and let you know.
I have been running my cards using 310.70, with the modded driver, for a couple of months and it has been rock solid.
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