Green line on my computer screen?

What does it mean when you have a horizontal purple line on your computer screen?

• I just have bought a Dell Inspiron Duo (the one where the screen flips so you can use it either as a tablet or a netbook) and I just got it for Christmas. I just turned it on for the first time today and when I first turned it on it had a purple horizontal line across my computer screen. My sister has received the same computer for Christmas as well and she didn't have that line on her screen. I have noticed that if another window is on top of that line it shows up on top of the window as well and it doesn't go away. What may be causing this?

• Answer:

  ring dell support and advise them of the problem. they should arrange to pickup the unit and repair it.