Go back to Win7, since that is where you want to be. Download and install the latest Driver Sweeper
utility. Download the latest Catalyst version from --> http://support.amd.com/us/gpudownload/Pages/index.aspx
Now, uninstall Catalyst in your control panel....choose everything except your USB drivers
.....reboot into safe mode. Run Driver Sweeper with elevated privileges (i.e. Run as Administrator), select Catalyst from list, analyse then clean.....reboot.
Install the new Catalyst version.....reboot a 2-3 times, try and re-enable CrossFire.
Let us know if it worked for you or not.
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