Arch Linux

barsch

Member

Registered: 2019-05-10

Posts: 3

Monitors over displayport not detected

I bought two Monitors and I try to connect them via a docking station to my lenovo p14s. This works if I use a HDMI cable but since the docking station only has one HDMI port at least the other monitor has to be connected via displayport.

When I start the laptop the screens are detected and show the grub menu as well as the bios. After choosing the distro in grub, the screens are not detected anymore. I've tried it with xrandr but this didn't work (as far as I am able to use this tool)

xrandr outputs that the displayports are disconnected.

xrandr
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384
eDP connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 309mm x 174mm
   1920x1080     60.00*+  48.00  
   1680x1050     60.00  
   1280x1024     60.00  
   1440x900      60.00  
   1280x800      60.00  
   1280x720      60.00  
   1024x768      60.00  
   800x600       60.00  
   640x480       60.00  
HDMI-A-0 disconnected (normal left inverted right x axis y axis)
DisplayPort-0 disconnected (normal left inverted right x axis y axis)
DisplayPort-1 disconnected (normal left inverted right x axis y axis)

seth

Member

From: Won't reply 2 private help req

Registered: 2012-09-03

Posts: 77,041

Re: Monitors over displayport not detected

Can you force-enable them?
https://raw.githubusercontent.com/torva … modedb.rst

Do they remain active if you boot "nomodeset" or the multi-user.target only (2nd link below)?

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How to upload text · How to boot w/o GUI · Disable Windows Fast-Start! · Fix your xinitrc

barsch

Member

Registered: 2019-05-10

Posts: 3

Re: Monitors over displayport not detected

Thanks for the answer but I don't understand how I can try to force them to stay on. What command do I have to run there?

seth

Member

From: Won't reply 2 private help req

Registered: 2012-09-03

Posts: 77,041

Re: Monitors over displayport not detected

It's not a command but a kernel parameter, https://wiki.archlinux.org/title/Kernel_parameters

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How to upload text · How to boot w/o GUI · Disable Windows Fast-Start! · Fix your xinitrc

barsch

Member

Registered: 2019-05-10

Posts: 3

Re: Monitors over displayport not detected

I tried all the things you proposed (nomodeset, trying to force them and switching the defualt.target) but none worked for me.

Also my setup is with an encrypted LVM. I doubt that this is part of the problem but who knows