Overview
By default, closing your laptop lid puts it to sleep. If you use an external monitor, you can change one setting so the laptop keeps running with the lid shut — known as clamshell mode. This guide shows how, plus how to set up the external display.
Run your laptop in clamshell mode with the lid closed and an external monitor.
Key Takeaways
- Change "When I close the lid" to "Do nothing" in Power Options.
- You can set it separately for battery and plugged-in.
- Connect the external monitor and set it as the main display.
- Ensure good ventilation, since a closed laptop can run warmer.
Why Use Clamshell Mode?
- A larger external monitor for a better viewing experience.
- A cleaner desk setup with the laptop closed and aside.
- Keep working uninterrupted while charging.
Method 1 — Power Options (Recommended)
1. Press Windows key + R, type powercfg.cpl, and press Enter.
2. Click "Choose what closing the lid does" on the left.
3. Set "When I close the lid" to Do nothing (for On battery and/or Plugged in).
4. Click Save changes.
Method 2 — Command Prompt (powercfg)
1. Open Command Prompt as administrator.
2. Plugged in: powercfg /setacvalueindex SCHEME_CURRENT 4f971e89-eebd-4455-a8de-9e59040e7347 5ca83367-6e45-459f-a27b-476b1d01c936 0
3. On battery: replace setacvalueindex with setdcvalueindex in the same command.
4. Apply: powercfg /setactive SCHEME_CURRENT (0 = do nothing).
Method 3 — Set Up the External Monitor
1. Connect the monitor (HDMI, DisplayPort, or USB-C) and power it on.
2. Press Windows key + P and choose Second screen only (or Extend).
3. Open Settings > System > Display, select the external monitor, and tick "Make this my main display".
4. Close the laptop lid — the external monitor keeps working.
Warning: A closed laptop has less airflow. Keep vents clear, and consider a stand for better cooling during long sessions.
Troubleshooting
Problem: The laptop still sleeps when closed.
Solution: Confirm "When I close the lid" is set to Do nothing for both battery and plugged-in, and that no other power policy overrides it.
Problem: The external monitor goes black when the lid closes.
Solution: Set the external display as the main display and choose "Second screen only" with Windows + P before closing the lid.
Problem: The laptop overheats.
Solution: Improve ventilation, use a laptop stand, and avoid heavy workloads with the lid fully closed.
Problem: The lid setting is missing.
Solution: It only appears on laptops. Update the chipset/power drivers if the option is absent.
Conclusion
Set "When I close the lid" to Do nothing and configure your external monitor as the main display to use your laptop in clamshell mode — just keep an eye on cooling with the lid shut.
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