Comment 31 for bug 252094

@Jan Girlich: I get "direct rendering: Yes", but I still experience low framerates for glxgrears.

I use Kwin, not compiz. After I turned off all effects, I see no more artifacts, however - with them on, I could see quite a bit in addition to the effects being absurdly slow. In particular, when I opened a new window, I just got interference pixels until the proper window showed up.