Alright i have a GIGABYTE 990XA-UD3 motherboard and for some reason the crossfire refuses to work. When I start up my computer it freezes on the desktop after catalyst is started and styas like that until I shut it off.
I got off the phone with sapphire tech support (dual 6870s) and after some crossfire cable interchanging and some single card starting, they said the problem is probably in the crossfire chip of the mobo.
Before I go for an RMA is there anything else I should try? Ati drivers are up to date, tried uninstall + reinstall, bios is up to date.
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Only thing I can think of is to verify that your DVI or HDMI cable to your monitor is connected to the graphics card on the PCIe x16 slot, not the 2nd graphics card on the PCIe x8 slot.