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"How to Set Up Dual Monitors for Your PC By Jedadiah Casey
Install a video card capable of outputting to two or more screens, if necessary.
Connect each monitor to an available output. Plug in the monitor and turn it on.
In the case of a laptop, connect a single monitor to the laptop's VGA or HDMI port, depending on your laptop configuration and monitor type.
Press and hold the Windows logo key.
Press the "P" key twice to enter monitor extended mode. This creates two independent displays where you can have separate application windows open on each monitor.
Release the Windows logo key.