I changed my resilution and it messed everything up

Troubleshooting a Black Screen After Changing Display Resolution to 4K on Your PC

Recently, I decided to experiment with my monitor settings and changed the display resolution to 4K. As someone new to using a PC, I wasn’t entirely sure about the process or the correct tags to use for troubleshooting. Unfortunately, this change resulted in a black screen, and I was unable to see anything on my monitor.

After waiting for a few minutes in case the system was processing the change, I still received no display output. To troubleshoot, I turned off my computer and restarted it. However, upon reboot, I encountered a “No Signal” message, indicating that the monitor was not receiving any input from the PC.

If you find yourself in a similar situation—changing your display resolution and then experiencing a black screen or “No Signal” message—here are some effective steps to resolve the issue:

1. Reset Display Settings Using Safe Mode

Enter Safe Mode: Restart your PC and repeatedly press the F8 key (or Shift + F8 on some systems) during startup to access Advanced Startup Options. Alternatively, if Windows 10 or later, force shutdown your PC three times to trigger Automatic Repair mode, then navigate to Troubleshoot > Advanced options > Startup Settings > Restart, and select Safe Mode.
Revert Resolution: Once in Safe Mode, right-click on the desktop and select Display Settings. Change the resolution back to a compatible value (e.g., 1080p or lower).
Restart Normally: Exit Safe Mode and restart your PC normally. Your display should now work correctly.

2. Use Keyboard Shortcuts to Switch Display Modes

Try Extending or Mirroring Display: On Windows, press Win + P to bring up the projector mode options. Select “Duplicate” or “Second screen only” to force the display to re-establish a connection.

3. Check Display Connections and Hardware

Ensure Cable Integrity: Make sure the HDMI, DisplayPort, or VGA cable is securely connected to both your monitor and PC.
Test with Another Cable or Monitor: If possible, try using a different cable or connect to another monitor to rule out hardware issues.