Problem with external display

Hello, Jeffrey B64

Welcome to the Microsoft community.

Thank you for your feedback. I understand that you are experiencing issues with the outside monitor. Here are some troubleshooting options:

1. Keep the HDMI cable connected

Press Win + P for 4 consecutive times (to trigger display mode cycle switching).

Wait for 10 seconds, the system will switch to “Second Screen Only” → “Copy” → “Extended” mode.

If you hear a beep but the screen is still black, try Press and hold the power button for 15 seconds to force power off, and repeat the operation after restarting.

2. Reset display settings blindly

Connect the HDMI cable (keep the external monitor black screen state)

Operate blindly in the following order (need to memorize the keyboard position):

Win + Pause → Tab ×5 → Enter → → → → Tab ×3 → Enter → Alt + F4

(Path: Open System Properties → Device Manager → Disable Graphics Card Driver → Close Window)

3. Safe Mode Repair

Force to enter Safe Mode:

Disconnect the HDMI cable and start the laptop normally.

Press and hold Shift while clicking Start Menu → Power → Reboot

Enter the recovery environment and select:

Troubleshooting → Advanced Options → Startup Settings → Reboot → Press 4/F4 to enter Safe Mode

Operating in Safe Mode:

Right click on the Start Menu → Device Manager

Expand Display Adapters → Right click on the graphics card driver → Disable Device

Connect HDMI after restarting the computer normally

Turn off HDR immediately:

Settings → System → Display → Windows HD Color → Close HDR

4. Disconnect the HDMI cable and log in to the laptop system.

Open the registry editor (Win + R enter regedit)

Navigate to:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\GraphicsDrivers

Create a new DWORD (32-bit) value named EnableHDR and set the value to 0.

Reboot and connect the HDMI

Solution 5: Reset via PowerShell

Disconnect the HDMI and log in to the system using the laptop screen

Run PowerShell as administrator

as administrator to execute commands:

Set-ItemProperty -Path “HKLM:\SYSTEM\CurrentControlSet\Control\GraphicsDrivers” -Name “HDR” -Value 0 -Force

Get-Service DisplayEnhancementService | Restart-Service

Reconnect HDMI

Disclaimer: Generally, modifying registry subkeys or work group is intended for advanced users, administrators, and IT Professionals. It can help fix some problems, however, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For further protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click How to back up and restore the registry in Windows - Microsoft Support to view the article. 

If none of the above methods work, it is likely that you have a hardware problem and we recommend you contact a professional computer repairer for assistance.

I look forward to your feedback.

Best Regards,

Aaron| Microsoft Community Support Specialist