this is what u will have to do...
1. Uninstall the amd driver and all of its components..
2. enter safe mode and remove all the remaining softwares files and registry files via DRIVER SWEEPER (its a software)
3. Reboot your pc and go back to normal mode
4. install the latest 12.4 driver .. it will install and don't worry it will show that its 12.3 installed