Did you do a thorough clean out of the Nvidia drivers before installing the ATI/AMD drivers ? Switching brands was once regarded as cause for a clean reinstall of Windows, but just doing a good clean-out of the old Nvidia drivers should do these days. Worked for me.
Try uninstalling the ATI driver (Catalyst Install Manager), and any un-installed Nvidia graphics driver components, via Programs and Features, and after rebooting run Driver Sweeper (or Driver Fusion if you do not have the original version). Select both Nvidia and ATI graphics drivers from the list and let DS/DF clean the remaininf files. Reboot again and try reinstalling the 13.1 driver.
Which Nvida card did you upgrade from ?
07:09 AM by