how to display in both laptop and monitor
1 Get the right cable. 2  When you connect an external monitor to a laptop computer, you have to run a cable between the two devices. 3  Make sure that you get a monitor cable that matches the sockets on your laptop and monitor. 4  Tell your operating system youâre using a second screen. Itâs easy to do this in Windows 8 by accessing Devices in your charms bar and setting your computer to project to a second screen. 2  On Macs*, the connection of an external monitor is automatically recognized. 3  Set up the orientation of the monitors.