I have tried Ubuntu 16.04, 16.10, and (currently) 17.04 on my Thinkpad P50 laptop. In each case I'm having a terribly hard time driving my external displays, especially with the laptop's dock.
When I plugin in an external display (either on the HDMI or DisplayPort) it's obviously recognized as the screen start flashing as they are automatically configured. The problem is that they don't stop. If I have the 'Displays' dialog open I can see it switch between 'Primary/Seconday' and 'Mirror/Mirror' as it swaps back and forth. If I unplug the external display, it will sometimes recover to a normal single desktop on the laptop's built-in display, but it looks like it will also sometimes crash gdm3 (I think? Something goes down and I have to restart anyway) I know the laptop drives the native display and two 1920x1200 displays on the dock in Windows, but I can't seem to get it to behave nicely in Ubuntu.
Questions:
- Maybe I can just force the display configuration and bypass what appears to be an autoconfig problem? I've used xrandr in the past, but I can't use it while the display is connected because everything is all flashy poopy. I guess I can make a hard config in the X config? I could use some suggestions for reading here.
- Perhaps I need a special driver? The free drivers for the nvidia card in my machine have cause really bad screen tearing even in 2d views, so I'm using the proprietary drivers (381.22).
- I'm getting a lot of crash reports for various things that seem related. /var/crash shows reports for auplink, plymouthd, gnome-shell, gnome-settings-daemon_gsd-xrandr, and xorg_Xorg, (and some others). Are these relevant perhaps?
- What more diagnostic steps can I take?