My recent personal experience with graphics cards seems to be different to other people - 16.04 has made my card work!
Several months ago I upgraded my gfx card to a radeon R9 380 because I wanted to play Fallout 4.
After installing the new card I had serious troubles with UM, even live disks wouldn't work properly.
This affected all the Ubuntus, so I moved to Manjaro for a few months.
A couple of weeks ago, I tried UM 16.04 beta, and now it's goodbye manjaro, welcome back UM!
I haven't tried any 3D gaming in UM - that's the only reason why I keep a windows partition on my drive.