If you own a Lenovo Thinkpad and experience screen flickering—monitor blacks out even if it’s turned on, static-like screen movement, or tearing— then it may just be due to a power-saving setting.

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Don’t fret, because it’s a common problem with Thinkpad notebooks. You’re also in luck, because it’s solvable with just a few terminal commands.

The solution

Note: this was tested on a Thinkpad X1 Extreme Gen 2 notebook running on an Ubuntu 20.04 distribution. I have an Intel UHD and Nvidia Geforce GTX1650 GPUs (Noveau driver). This solution solved my screen’s flickering for the time being.

The solution is to disable Intel’s Panel Self Refresh (PSR) setting.1

  1. First, check if PSR is actually turned on:

     sudo cat /sys/kernel/debug/dri/0/i915_edp_psr_status

    This should show:

     Sink support: yes [0x01]
 PSR mode: enabled
 PSR sink not reliable: no

  2. You can disable it by editing /etc/default/grub:

     gedit admin:///etc/default/grub

    A quick note: don’t type sudo gedit /etc/default/grub even if some tutorials tell you to. Using sudo to edit graphical settings is unsafe due to elevated privileges!2 Read more from the Ubuntu wiki.

  3. Now, look for the line that says quiet splash and append i915.enable_psr=0 in front of the last quote. It should look like this:

     # /etc/default/grub (before)
 GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
 # /etc/default/grub (after)
 GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i915.enable_psr=0"

  4. Save the file and type:

     sudo update-grub

    And reboot your computer.

  5. After rebooting, check if PSR has been disabled:

     sudo cat /sys/kernel/debug/dri/0/i915_edp_psr_status

    It should now show:

     Sink support: yes [0x01]
 PSR mode: disabled
 PSR sink not reliable: no

Explanation

Panel Self Refresh (PSR) is an optimization to reduce the power consumed by your computer, especially the chip. It’s directly tied to how a monitor displays contents to us.

Most monitors have a 60 Hz refresh rate, so every second it updates what you see on the screen 60 times. It is good if you’re viewing dynamic content like games, scrolling, or watching movies. But it’s not that efficient when display is static: reading from a website, idle time, etc.

PSR addresses the latter by “remembering” a few frames into memory (the frame buffer) so that refreshing takes less work. Screen flicker may be due to the memory leaking from the frame buffer, causing us to see unsynced content. By disabling it, we lose that optimization at the cost of power efficiency—a price to pay to remove that screen flickering.

Other solutions

  • Aside from disabling PSR, one solution also suggested turning off Frame Buffer Compression (i915.enable_fbc=0) and mode setting (i915.modset=0). Similar to the command above, you just need to append these to the grub parameter above:

      # /etc/default/grub
  GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i915.enable_psr=0 i915.enable_fbc=0 i915.modset=0"
  • Updating your graphics drivers may also be another option. However, this didn’t work for me. I switched from the Noveau driver to nvidia-470 (proprietary, tested) and the flickering still showed up.
  • Lastly, if you’re on Windows, you can search for the Intel Graphics Command Center, head to the Power tab, locate the Panel Self Refresh setting and toggle the disable button.

Did it work? Please let me know in the comments below! If you also solved your problem using a different method, please let me know as well!

Footnotes

  1. The Arch Linux documentation is a good resource for troubleshooting the Intel driver and cross-referencing your Google search results. Even though I am using Ubuntu, some of which still applies. You can also check the corresponding Linux kernel bug report for more info. ↩

  2. If you are using Ubuntu 16.04 or below, you can use gksudo like so: gksu gedit /etc/default/grub. But since it’s already removed in 18.04, you can use pkexec gedit /etc/default/grub (long-term method). I am only using the admin route because it doesn’t require any new installations. Read more from this article. ↩