Sounds like Windows Update is installing/changing the graphics driver. If you look in Device Manager / Display you will probably see AMD has Microsoft driver.
To stop this you can prevent Microsoft from install any graphics driver:
This does not effect the security, quality, patch, or any other type update...they are presented as normal.
In short...you don't have to worry about WU installing (changing) AMD graphics drivers.
This is done through group policy:
Type gpedit in the search bar...follow > Computer Configuration > Administrative Templates > Windows Components > Windows Update
On the right side scroll to Do not include drivers with Windows Update policy and double click it. Select the ENABLED option.
Click 'Apply' then OK.
Reboot your computer.
