Originally Posted by Sean.
Hi there I have just bought a new screen for my computer. I am using this screen to watch my movies / catch up programs. The problem I have is my main monitor is now displaying the desktop whilst the secondary screen is in use. What damage and effects does this have on my LCD screen? and what can I do to avoid / reduce this?
That won't damage anything.
If you want only one display at a time, then you can press Windows Key + P to bring up the screen switcher, and select if you want to Duplicate, Extend (which is what you have right now), or display only on one of the displays.
You can also do that by right clicking the desktop -> Screen Resolution -> select the appropriate option from the dropdown.
Though why wouldn't you want to have both displays going? It's great for productivity.