AMD proprietary drivers for 3.0

[firenice03]

I second toredale...

If you were my neighbor, I would personally install Linux Lite 2.6 for you, and then upgrade you from there to Linux Lite 2.8.  I think you would be happier with the result.  And you would still have just over 2.5 years of support left.  That's also 2.5 years for AMD to decide if they want their proprietary drivers to be a part of Ubuntu again.

Remember the issue you having; whether its a black line, screen tearing, a few other known issues isn't a fault of LL3.0 its any Ubuntu 16.04. AMD/ATI/Radeon support isn't there as it was in Ubuntu 14.04 (LL2.x series) the easiest and most stable resolution(IMHO) would be install 2.6 then 2.8 and see if support returns..
If you really want LL3.0 or any 16.04 you'll be chasing drivers... And truthfully the fault isn't Ubuntu, AMD is no longer maintaining the driver..

Some info to get you started.. I don't know your exact chip/model so the info is semi generic..
http://www.phoronix.com/scan.php?page=ar...-amd&num=1
https://help.ubuntu.com/community/RadeonDriver
http://support.amd.com/en-us/kb-articles...Notes.aspx

Good luck and keep us posted