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I have an Asus EEE PC 701 laptop with 7" 800x480 screen running Debian Jessie with Openbox as a WM. As I try to maximally use all the capabilities of this laptop, I'm searching for a way to get a dynamically-configurable dual monitor setup, so that when I feel limited by this laptop's small screen, I can just attach an external monitor and it will work. However, there seems to be little or no information about it, keeping in mind that I have integrated Intel GPU with one VGA output. The question is - what should I install&&configure in order to just plug in a monitor in my laptop and instantly have my workspace extended?