Running Kubuntu 16.04 with nvidia-367, I'm experiencing redraw glitches, especially on my external monitor (connected with VGA). When scrolling, it is clearly visible that the window is drawn from two triangles, and the diagonal line connecting the two is apparent. The effect is less visible on the 1920x1080 laptop display than on the 1680x1050 external monitor, but it is present on both.
For example, it happens when scrolling maximised browser window, or when scrolling a PDF in Okular; but also other times.
I don't see the same symptom when using the default graphics drivers.
I have tried changing the compositor settings in "System Settings". I'm using "Accurate" scale method, "OpenGL 3.1" rendering backend with "GLX". I have tried all the different settings for vsync.
Is this a known problem?
Small update: I installed Plasma 5.8 (from Kubuntu backports) and nvidia-340. (After doing so I had to replace sddm with lightdm because sddm would segfault with the nvidia drivers installed.) Now I have the same problem but on the laptop monitor (LVDS-1-1) instead of the external monitor (VGA-1-1).