How to Hook Up a Second Monitor on an HP TouchSmart Computer. The HP TouchSmart line of computers features a touch screen and an all-in-one design that's comparable to tablets.

Using a laptop as a monitor for another computer allows you to not only mirror your computer's screen on the laptop but also extend it, meaning you can show different content on both screens.

On your main PC, use the Windows Key + P shortcut to open your PC's display projection settings. Select Extend from the options list, allowing you to use your laptop as a second monitor when you ...