I have installed a second 5870 in my pc made sure its hooked up properly but when it comes to getting it working I don't know how I used to run SLI on my last pc and that seemed simple but for crossfire I don't what to do. Windows knows the second card is there but labels it 'unknown VGA device' I assumed it needed to have drivers installed so installed the latest 10.9 ones but now I can see the 'unknown VGA device anymore' (after reboot) and there seems to be no option to start crossfire nor does CCC seem to think there is a second card. Pls Pls help.
CPU-i7 930 @4.01GHz
GFX-2x 5870 @ standard clock
PSU- Corsair 750 watt
AMD's driver installation either goes just as smoothly as Nvidia's or get ornery. The best-case scenario is that you plug the graphics cards into the mainboard, connect them with a CrossFire bridge, start the system, and install the driver. The worst-case scenario is that cards aren’t recognized by the drivers. If you drop back to only having one card inserted, the driver will install, but as soon as the second card is plugged in, the Catalyst Control Center (AMD's graphics driver interface) returns error messages complaining about missing files, preventing access to the CrossFire settings.