I have ThinkPad L14 running clean new install of Ubuntu 25.10 desktop.
I have connected it to Lenovo Thunderbolt 3 docking station with thunderbolt cable.
Dock is connected to two monitors (displayport), Ethernet and 3.5 mm audio cable to speaker.
Problem Description:
I have disabled the built in laptop screen and kept two connected monitors active.
The problem is when turning the laptop on the two connected monitors are blank and log-in screen is on the built in monitor (which I have disabled in the the settings)!
I have to open up the lid and get up to see where I am clicking. Once I log-in, the built in screen goes blank and the two external monitors start working fine. (one of them being primary as I see dock on the left and top).
It is minor thing.
But I’m assuming I’m missing something here in settings.
Any ideas?
I’ve been struggling with a similar thing trying to get an Apple MacBook Pro 13,2 to work in clamshell mode (with 2 external monitors attached via USB-C). During boot, the LUKS Crypt screen would not show on the external monitors, so I’d have to blind type the disk encryption password in order to be able to log in.
The following works for me ( the Mac has an Intel i915 GPU ), so I created the file /etc/dracut.conf.d/10-uvcvideo.conf with the following contents
add_drivers+=" uvcvideo i915 "
I then rebuilt the initrd filesystem dracut --regenerate-all --force --hostonly
Make sure you have a good backup before you begin and have the reinstallation media to hand too. I’ve been getting good practice in rebuilding my system.
lspci -k may help you see which video/graphics drivers you need to add.
(my original post, I suggested using lsmod | grep video but the above is better).
Having done that, you then need to update grub sudo update-grub
I wouldn’t recommend disabling the internal display ( unless you will always have a Display Port adapter connected ). I’ve tried adding two display port adapters in the configuration, but that doesn’t work as expected either ( the second adapter isn’t recognized and when gnome starts, I end up with a 640x480 second monitor ). If you start the laptop without a display port connected monitor, you also end up with a second 640x480 monitor - which you will want to display from the display settings in gnome.
ls /sys/class/drm shows the type of adapters your system understands e.g. card1-DP-1 for DP-1 etc.
DRM drivers also add options to enable or disable outputs:
‘e’ will force the display to be enabled, i.e. it will override the detection
if a display is connected. ‘D’ will force the display to be enabled and use
digital output. This is useful for outputs that have both analog and digital
signals (e.g. HDMI and DVI-I). For other outputs it behaves like ‘e’. If ‘d’
is specified the output is disabled.
Thank you for your help. Yes, I need to be able to remove it from dock without any hassles. So, I think I will live with this minor annoyance (until/if it gets fixed properly).
As it is I don’t have much time to keep messing with the set-up.