6.3rc5 screen flicker (AMDGPU)

Introduction

This tutorial addresses the common issue of screen flickering on Linux with the 6.3rc5 kernel, specifically for users of the Thinkpad T14s equipped with the AMD Gen 3 and AMD 6850u APU. By following the steps outlined below, you can troubleshoot and resolve this flickering issue, enhancing your user experience.

Step 1: Update Your System

Ensure your system is fully updated to avoid compatibility issues.

• Open a terminal.
• Run the following commands to update your package list and upgrade installed packages:

  sudo apt update
  sudo apt upgrade
  

Step 2: Check Current Kernel Version

Verify that you are using the correct kernel version.

• In the terminal, execute:

  uname -r
  

• Ensure the output matches the 6.3rc5 kernel version. If not, consider switching to this kernel or updating.

Step 3: Modify GRUB Configuration

Adjustments to the GRUB configuration can help resolve flickering.

• Open the GRUB configuration file in a text editor:

  sudo nano /etc/default/grub
  

• Find the line that starts with GRUB_CMDLINE_LINUX_DEFAULT and add the following parameters:

  amdgpu.dc=1
  

• The line should look something like this:

  GRUB_CMDLINE_LINUX_DEFAULT="quiet splash amdgpu.dc=1"
  

• Save and exit the editor (Ctrl + O, Enter, Ctrl + X).

Step 4: Update GRUB

After modifying the configuration, update GRUB to apply changes.

• Run the following command in the terminal:

  sudo update-grub
  

Step 5: Reboot Your System

To ensure all changes take effect, reboot your computer.

• In the terminal, type:

  sudo reboot
  

Step 6: Test for Flickering

After rebooting, observe your screen for any flickering issues.

• If the flickering persists, consider resetting the display settings.
• You can also try adjusting the refresh rate in the display settings of your desktop environment.

Conclusion

By following these steps, you should be able to resolve the screen flickering issue on your Thinkpad T14s with the AMD 6850u APU running Linux 6.3rc5. If problems continue, consider searching for additional driver updates or consulting forums for specific tweaks related to your hardware configuration. Keeping your system updated and adjusting GRUB settings are key strategies in maintaining optimal performance.