Go to Windows Update...run it. If you do not get the message "There are no updates for your computer"...then keep installing all available. Keep running WU until you get the "no updates" message....then install the AMD graphics driver. Win8.1 (and Win7) must be fully updated before attempting to install any AMD driver.
I would try the 16.11.5 drivers...the new ones have issues for some/most people > http://support.amd.com/en-us/download/desktop/previous/detail?os=Windows%208.1%20-%2064&rev=16.11.5
Install > Clean Install AMD Graphics Drivers