I have 3 screens currently active, running through one of my ASUS R9 270X graphics cards, (I did have 2 in but I was getting problems with the display and the ASUS/AMD proprietary drivers crashed my system.) I now have Ubuntu Mate 15.05 running through a single 270x, which is working fine (It crashes when I try to use 4 for some reason - the screen goes all mosaic on me). The problem that I am having now, is Icons are missing from my display, but show up on where the 4th monitor should be on a black background, when I do CTR-ALT-Arrow Key. Plus also parts of one of my active screen is dead. I can have a window open on it, and only half or the window responds (the right side). I dont know what is causing this, does any one have any clues?
xrandr
output:
warren@RIVE:~$ xrandr
Screen 0: minimum 320 x 200, current 3360 x 1950, maximum 16384 x 16384
DisplayPort-0 connected 1680x1050+0+900 (normal left inverted right x axis y axis) 474mm x 296mm
1680x1050 60.0*+
1280x1024 75.0 60.0
1440x900 75.0 59.9
1024x768 75.1 60.0
800x600 75.0 60.3
640x480 75.0 60.0
720x400 70.1
HDMI-0 disconnected (normal left inverted right x axis y axis)
DVI-0 connected 1680x1050+1680+900 (normal left inverted right x axis y axis) 474mm x 296mm
1680x1050 60.0*+
1280x1024 75.0 60.0
1440x900 75.0 59.9
1024x768 75.1 60.0
800x600 75.0 60.3
640x480 75.0 60.0
720x400 70.1
DVI-1 connected 1440x900+1920+0 (normal left inverted right x axis y axis) 408mm x 255mm
1440x900 59.9*+ 75.0
1280x1024 75.0 60.0
1152x864 75.0
1024x768 75.1 70.1 60.0
832x624 74.6
800x600 72.2 75.0 60.3 56.2
640x480 75.0 72.8 66.7 60.0
720x400 70.1