Hi, I'm having problems with having both the built-in display of my Thinkpad T440s and an external monitor working. If I boot the system without the external monitor connected, the built-in display works, but as soon as I connect the external monitor the external monitor starts working and the built-in display goes blank. If I boot with the external monitor connected, the initial boot screens (bios, grub...) show up on the built-in display but as soon as I get to the GDM login screen it goes blank and only the external monitor works.
In any of these cases, even if I disconnect the external monitor after the built-in display stops working, it doesn't start working again (i.e. it is not "re-enabled"). Both of the displays are properly enabled in the Displays configuration screen (I've tried with both primary-secondary and secondary-primary configurations, the problem is the same). Do you have any ideas about how can I solve this problem? Is it a known issue with the T440s? This is the debian version that I'm using: 3.16.0-4-amd64 #1 SMP Debian 3.16.7-ckt7-1 (2015-03-01) x86_64 GNU/Linux Thanks in advance, André.
