We're sorry you are having trouble. It could be the cable, monitor or something amiss with the refresh rates. Can you try a different cable or monitor? do any other software cause the same issue?
Tutorial for proper driver installation.
1-Load windows with only your primary graphics card plugged in.
2-Disable any and ALL anti-virus/malware protection.
3-Download and Run the latest drivers from AMD.com (Omega drivers do not have Uninstall built in, you have to do it through add/remove, which is okay)
3.5. AMD now has a nice Uninstall tool which should work as a better alternative- http://support.amd.com/en-us/kb-articles/Pages/AMD-Clean-Uninstall-Utility.aspx
4-Choose to Uninstall/express (may not be available in newest version, download an older version) the existing drivers, and AMD folder
5-Restart the computer.
6-Disable any and ALL anti-virus/malware protection.
7-Run the latest drivers from AMD.com
8-Choose to Install/Express the drivers
9-Restart. Confirm settings are working in windows.
10-Shutdown and add 2nd/3rd cards for Xfire.
11-Respond to this ticket if you have any further questions
** If you have nvidia drivers on your computer, you might need to run the Uninstall feature of Nvidias driver as well.