Unfortunately, on 16.04 the
fglrx drivers became deprecated.
You'll need to use the open-source
amdgpu driver instead.
From the release notes:
The fglrx driver is now deprecated in 16.04, and we recommend its open
source alternatives (radeon and amdgpu). AMD put a lot of work into
the drivers, and we backported kernel code from Linux 4.5 to provide a
When upgrading to Ubuntu 16.04 from a previous release, both the fglrx
driver and the xorg.conf will be removed, so that the system is set to
use either the amdgpu driver or the radeon driver (depending on the