Ubuntu 17.10单独连接USB DisplayLink显示器无法开机显示求助

Hey there, let's tackle this annoying DisplayLink issue you're facing. Since it works fine when you boot with an HDMI monitor connected, the problem is likely that Ubuntu isn't prioritizing or loading the DisplayLink drivers early enough during startup. Here are some targeted fixes to try out:

1. Ensure DisplayLink Modules Load Early in the Boot Process #

The udl (DisplayLink kernel module) might not be included in your initramfs, which means it loads too late for the system to detect the monitor on boot.

• Run this command to add the module to your initramfs load list:

  echo "udl" | sudo tee -a /etc/initramfs-tools/modules
  

• Update the initramfs to apply the change:

  sudo update-initramfs -u
  

• Reboot your system and test if the DisplayLink monitor works on startup.

2. Force Video Output to DisplayLink via GRUB #

By default, Ubuntu might be prioritizing your GTX 1070's HDMI output even when it's disconnected. We can tweak GRUB to force it to use the DisplayLink adapter:

• Edit the GRUB configuration file:

  sudo nano /etc/default/grub
  

• Find the line starting with GRUB_CMDLINE_LINUX_DEFAULT and modify it to include DisplayLink settings (replace 1920x1080 with your monitor's actual resolution):

  GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset video=udl:1920x1080"
  

• Save the file (press Ctrl+O, hit Enter, then Ctrl+X), then update GRUB:

  sudo update-grub
  

• Reboot and check if the monitor shows up.

3. Manually Configure Xorg to Prioritize DisplayLink #

If GRUB tweaks don't work, we can create an Xorg configuration file to explicitly set DisplayLink as the primary display:

• Create a new Xorg config file:

  sudo nano /usr/share/X11/xorg.conf.d/20-displaylink.conf
  

• Paste the following content (again, replace 1920x1080 with your monitor's resolution):

  Section "Device"
      Identifier "DisplayLink"
      Driver "modesetting"
      Option "AccelMethod" "none"
  EndSection
  
  Section "Monitor"
      Identifier "DisplayLinkMonitor"
  EndSection
  
  Section "Screen"
      Identifier "DisplayLinkScreen"
      Device "DisplayLink"
      Monitor "DisplayLinkMonitor"
      DefaultDepth 24
      SubSection "Display"
          Depth 24
          Modes "1920x1080"
      EndSubSection
  EndSection
  

• Save and exit, then reboot your system.

4. Check NVIDIA Driver Compatibility #

The closed-source NVIDIA driver for your GTX 1070 might be conflicting with the DisplayLink udl module. Try switching to the open-source Nouveau driver to test:

• Open Software & Updates from the applications menu.
• Go to the Additional Drivers tab.
• Select the option labeled "X.Org X server - Nouveau display driver" and click Apply Changes.
• Reboot and see if the DisplayLink monitor works on startup. If it does, you can either stick with Nouveau or try updating your NVIDIA driver to the latest stable version compatible with Ubuntu 17.10.

内容的提问来源于stack exchange，提问作者Paul Gigioli