[Solved] PC Not Booting or BIOS Inaccessibility After Disabling CSM (Windows 11)

Have you recently disabled Compatibility Support Module (CSM) in your PC’s BIOS and found yourself in a tricky situation where your computer won’t boot, or you can’t access the BIOS anymore? Don’t panic. We’ve got a step-by-step guide to get your system back on track.

Why Disabling CSM Causes Issues

Before we jump into the solutions, let’s understand why this problem occurs. Disabling CSM can lead to boot problems because some operating systems and hardware components may rely on CSM to function correctly. When it’s disabled, your PC may not recognize these components, leading to boot failures and BIOS inaccessibility.

How To Fix PC Not Booting or BIOS Inaccessibility After Disabling CSM

Use an HDMI Monitor

If you’ve been using a display port to connect your monitor, switch to an HDMI connection. In some cases, disabling CSM settings can affect the display port output, causing it not to function correctly. Using an HDMI connection ensures your display works seamlessly.

Clear CMOS

If you’re still unable to access the BIOS to re-enable CSM, you can try clearing the CMOS (Complementary Metal-Oxide-Semiconductor) settings. This will reset your BIOS settings to their defaults.

To clear CMOS, follow these steps

  • Turn off your PC and unplug it from the power source.
  • Open your computer case to locate the CMOS battery on the motherboard.
  • Remove the CMOS battery for a few seconds and then put it back in. This process will reset your BIOS settings.


After switching to an HDMI connection or clearing CMOS, restart your PC. During the boot-up process, repeatedly press the key that grants access to your BIOS/UEFI settings (usually Del, F2, F12, or Esc). This time, you should be able to get in.

Re-enable CSM

  • Once you’re in the BIOS/UEFI settings, navigate to the “Boot” or “Advanced” section (the specific location can vary depending on your motherboard).
  • Locate the CSM setting and re-enable it. Save the changes and exit the BIOS.

Finally, restart your computer to see if it boots up correctly. With CSM enabled and your HDMI connection, your PC should now function as expected.

[Solved] PC Not Booting or BIOS Inaccessibility After Disabling CSM

By following these steps, you’ll resolve the PC booting issues and regain access to your BIOS settings after disabling CSM. This crucial fix will ensure your system runs smoothly and provide you with a hassle-free computing experience. Happy troubleshooting!

Masab Farooque is a Tech Geek, Writer, and Founder at The Panther Tech. He is also a lead game developer at 10StaticStudios. When he is not writing, he is mostly playing video games