Tearing is the big one. As soon as a game starts playing, I get a whole bunch of horizontal lines that will continuously shift and flicker as the screen refresh

Tearing is the big one. As soon as a game starts playing, I get a whole bunch of horizontal lines that will continuously shift and flicker as the screen refreshes. It doesn't happen with regular video, but it happens with Kerbal Space Program (not that graphically intensive) and PCSX2 (very graphically intensive). I don't know nearly enough to say exactly where the problem is, but one of the more frustrating aspects is that there is next to no documentation on troubleshooting such issues. It might be a problem on my end for all I know, but all that I can tell is that before updating to Ubuntu 16, fglrx worked okay, and after updating, playing games is extremely aggravating. I would like to say that the drivers are a hell of a lot better than they were in 2011, though - last time I had to deal with the open-source drivers, it was "Display minimum functionality so that you have the ability to install the proprietary drivers," and HDMI support was horrifyingly bad. These days, it's "Works for everything except gaming," which is completely serviceable for me.