I just added a second MSI 660 ti PE to my rig, both cards work fine by themselves, but when I enable sli it locks up within a second of starting a game. When I run EVGA Scanner only one GPU is working, I have uninstalled and reinstalled the driver, removed and replaced the cards, I am fairly sure it is a driver or configuration issue rather than a hardware issue, both cards work and I flashed the bios on one card so they match. Any help would be appreciated.