To show three different screens, all three displays must be set to Extend, not Duplicate.
- Open Start > Settings > System > Display.
- Select each display in the diagram and use the display mode dropdown.
- Set the laptop screen and both external monitors to Extend desktop to this display.
- Arrange the monitor icons so they match the physical layout on the desk.
- If needed, select the laptop display and keep it as the main display.
If windows are replacing each other on one monitor, that usually means one of the displays is currently set to duplicate instead of extend.
If only two displays can be active at once, the limiting factor is usually the graphics hardware or the dock/connection method:
- Some laptops and graphics adapters support only two displays at one time.
- If the device has only one video output port, it normally supports only one external monitor unless a docking station or USB adapter adds another video output.
- A display splitter cannot extend to multiple monitors; it only duplicates the same signal.
For a docked setup, make sure each monitor is connected as its own display output from the dock, then configure them in Display settings.
If the setup previously worked and stopped working, try these steps:
- Press Windows logo key + Ctrl + Shift + B to reset the graphics driver.
- Restart the PC from Start > Power > Restart.
- In Display settings, confirm all screens are detected and each external monitor is set to Extend desktop to this display.
- If the issue started after an update, open Device Manager > Display adapters > right-click the adapter > Properties > Driver > Roll Back Driver if that option is available.
References
- Troubleshoot external monitor connections in Windows
- Troubleshoot external monitor connections in Windows
- Use Surface Dock 2
- Error message when you configure the display settings to try to use three or more displays on a laptop that is running Windows 7 and Windows 8: "Unable to save display settings"