Right now, I have my laptop using two screens: the laptop screen and 2nd monitor. The 2nd monitor extends the desktop. I would like to be able to hook up a 3rd monitor to duplicate only what the 2nd screen displays. Is this possible and if so, how?
Logically speaking, you should be able get a splitter that takes the input going to the screen you want to duplicate and gives the signal to both monitors. Identical or near identical monitors may be necessary.
Many video cards support 2 monitor outputs max (even if they have say 4 connections) which is most likely the case with a laptop.
ie, something like this: http://www.amazon.com/HDMI-Splitter-Premium-Cable/dp/B000FMJLQC