Comment 24 for bug 1634449

I've been seeing this as well (currently testing on Linux Mint Cinnamon)

I have an Asus UX501V Skylake laptop, with secondary display connected via HDMI.

A little black square with a few pieces of white trash appears in the top corner of the *current* display (the display where the mouse is), every time I move the mouse to the other display. It appears and disappears instantly, as if it is there for one frame only.

Kernel is: 4.8.0-040800-generic
Primary display is Hi-DPI, secondary is 1920x1280

Also, as I type in my console window, the same square appears when I type. But only on the first key press.

I disabled the Intel driver and am running on the latest 375.10 NVIDIA driver to see if things would be better, but they aren't.

Will try to update the kernel soon, but having issues with current builds atm.