My Monitor Won't Work?

External monitor wont work!?

• Ok so i've been trying to get an external monitor to work with my laptop for hours now. The monitor has power and is working because before I plug it into my laptop it says "check video cable" but when I plug it in it says "monitor going to sleep" like it would on the desktop when the tower was off. I have tried everything. My drivers are up to date, I went into the display settings and set up for a second monitor but its not detecting any. I tried all the fn + f5 and all those. On my laptop its F keys have little pictures of what they do with fn and f6 shows the change to external monitor one but it doesn't do anything. I tried all the sites for my laptop and the monitor even, checked for drivers everything but it just wont work for me. All I can think of is... My laptop is an Alienware so it came with a bunch of weird extras and all that. Well it crashed a while back so I had to reinstall windows, it came with vista 64 but I upgraded to windows 7 64. When I reinstalled windows it only had the basic windows and none of the extra alienware things it had at first. Any ideas how I can get this monitor to work for me?

• Answer:

  There should be a key on the keyboard to switch. It will say either CRT/LCD or a picture of a monitor. Press that. It might be a FN key.