T420 - Can't use DisplayPort with integrated graphics
Posted: Mon May 02, 2016 2:50 am
Hi there, got a fancy new monitor (a Dell P2715Q), but I seem to be unable to get it to work properly.
My laptop comes with the NVS4200m, but I disable it since it is not compatible with OS X. However, when it is disabled, I seem to be completely unable to use the DisplayPort.
I checked with a Fedora live USB, and what happened was:
Integrated graphics: Monitor does not work. xrandr does not show the DisplayPort at all.
Nvidia Optimus: The monitor connects! Ports display in xrandr.
Dedicated graphics: The Fedora live USB goes to a black screen, can't see anything.
Edit: Also checked with a Linux Mint live USB, same thing - DP is not even present in xrandr when using integrated graphics.
My laptop comes with the NVS4200m, but I disable it since it is not compatible with OS X. However, when it is disabled, I seem to be completely unable to use the DisplayPort.
I checked with a Fedora live USB, and what happened was:
Integrated graphics: Monitor does not work. xrandr does not show the DisplayPort at all.
Nvidia Optimus: The monitor connects! Ports display in xrandr.
Dedicated graphics: The Fedora live USB goes to a black screen, can't see anything.
Edit: Also checked with a Linux Mint live USB, same thing - DP is not even present in xrandr when using integrated graphics.