What mr91 said, and also the game is not optimized to use both SLI cards, I have
Mobo: MSI Z97-Gaming 7
Case: Phanteks Enthoo Pro Series
Monitor: BenQ GL2760H Black 27" 2ms
GPU: (2) EVGA 04G-P4-2974-KR GeForce GTX 970 4GB ACX 2.0 OC Edition in SLI
Keyboard: RAZER Blackwidow Ultimate Stealth Edition Gaming Elite
Mouse: Logitech G602 Wireless
Headset: Astro A50s
Thermal Paste: Antec Formula 7
CPU: Intel Core i5-4690K OC'ed @ 4.0 GHz
CPU Cooler: CORSAIR Hydro Series H105
SSD: Kingston SSDNow V300 240GB
HDD: Western Digital Blue WD10EZEX 1TB
OS: Microsoft Windows 8.1 Pro
RAM: G.SKILL Ripjaws Series 8GB (2 x 4GB) 1600MHz
PSU: CORSAIR CX series CX750
I still get around 50-70 FPS. HOWEVER if you look at a GPU monitor, only about 20-40% of the cards are being used, this is extremely inefficient. As we could be pushing a lot more into the game.