How to Fully Disable the Internal Display on ASUS ROG Laptops (Strix SCAR, Zephyrus, etc.) for External Monitor Firmware Updates

Many external monitor utilities (AOC G-Menu and others) require that Windows detect only one active display in order to update firmware. Simply disabling the laptop’s internal panel in Device Manager does not work because Windows still enumerates the built-in display even when “disabled.”

After testing different approaches, I found a reliable method on the ASUS ROG Strix SCAR 16 that also applies to most ASUS laptops equipped with a MUX switch.

This procedure fully disables the internal panel at the firmware/GPU level, so Windows truly sees only the external monitor.

Step-by-Step Guide

1. Change lid-close behavior

1. Open Control Panel
2. Go to Power Options
3. Click Choose what closing the lid does
4. Set When I close the lid to Do nothing (for both battery and plugged-in)

This prevents the system from going to sleep when you close the lid.

2. Close the laptop lid

After closing it, you will operate solely on your external monitor.

3. Switch the laptop to dGPU-only mode (Ultimate Mode)

1. Open Armoury Crate
2. Go to Devices
3. Select your laptop (icon on the left)
4. Open GPU Performance
5. Change GPU Mode to Ultimate

“Ultimate” mode forces the system to run on the discrete GPU only. On many ASUS laptops, this automatically disables the integrated GPU and the internal display connected to it.

You will be prompted to restart.

4. Restart with the lid closed

After rebooting in Ultimate mode (lid still closed):

• The internal display is no longer active
• Windows does not list it in Device Manager
• Only your external monitor appears as a connected display

This is precisely what firmware utilities require. You can now run tools like AOC G-Menu without the “Please connect only one display” error.

Why this works

The internal screen on most ASUS ROG laptops is wired to the integrated GPU. When you switch to Ultimate (dGPU-only) mode, the iGPU is disabled at the hardware/firmware level, which also disables the internal panel. Windows then sees only the dGPU and the external display attached to it. This is fundamentally different from using Device Manager, which only disables drivers—not hardware enumeration.

Reverting the change

If you want the internal display back:

1. Reopen the lid
2. Open Armoury Crate
3. Switch GPU Mode back to Standard or Optimized Hybrid
4. Restart

Your internal screen will function normally again.

Conclusion

If your external monitor’s firmware update utility refuses to run because multiple displays are detected, this method is a practical and reversible way to make Windows see only the external monitor. It’s especially useful on ASUS ROG laptops with a MUX switch such as the Strix SCAR, TUF, Zephyrus, and most 2022–2025 ROG models.