as long as you did not remove the built in Microsoft driver, and all device manger does is remove the cards driver its not a full complete uninstall of the amd loaded stuff
if your not careful doing things from the device manager you can see here what you can end up with as this guy found out
http://www.tomshardware.com/answers/id-2249397/hardware-dysfunction.html
with most all programs and software its best to read the notes for what they got for it like most all have a install/uninstall tool in them to properly remove there stuff quick and easy and safe