Specs: OS: Windows 7 sp1 M/B: ASUS Crosshair V Formula CPU: AMD Phenom II x6 1100T RAM: G.SKill RIpjaws 8gb (2 x 4gb) DDR3 1866 GPU: x2 ASUS GTX570 DCU-II PSU: Corsair HX 850W both cards running 313.95 beta drivers, however, I have had this issue with 310.90 WHQL drivers as well. When enabling SLI through Nvidia Control Panel, the screen flickers, resets resolution to 1280x800 and can only be set as high as 1280x1024. Device Manager shows a Code 43 (Windows has stopped this device because it has reported problems.) on the first card, while the second reports no problems. Nvidia Control panel reports an error stating: "You are not currently using a display attached to an nvidia GPU." Upon restart, all issues persist, however both cards now show up as "Standard VGA Adapter". Drivers reinstall normally, until I try to enable SLI and I'm back to square one. I have had SLI working on the system before, I have run both cards individually without issue, as well as swapped position of the cards and SLI bridge. Both cards show green power LEDs. I uninstalled all nvidia software, as well as remove it from the registry, cleared CMOS, with no progress. Could it be a driver conflict? I have heard of audio drivers messing with SLI. Ideas? Any help would be appreciated. Thanks, Pat. UPDATE: outdated BIOS seems to have been causing it, updated to 1703 and things are running smooth.