Caution 4 Maxi screens even with 2 cards

Hello,
J bought a second GTX670 card to replace my HD6950 card, and avoid mixing AMD, NVIDIA.
With a GTX 670 for 3 screens and surround AMD HD6970 2 screens car driver not installed (crash Blue Screen)

J have gifts to buy a second GTX 670 thinking I could connect all my screens Flight Simulation, thinking use First card for surround and second board for 4 additional screens.

Well no 4 maxi, Surround and SLI mandatory .and Verion Driver Nvidia 314 FSX plant, installation of version 306.

Otherwise ok display quality, for those who want 3D ok, my colleague uses the 3D (with glasses) smoothly with one screen 27 inch.

GOOD STUFF