Control manu is lock dell problem

Do you mean the controls on the screen are locked (brightness, contrast, horizontal & vertical settings, etc?)

I had this problem once - all you need to do to unlock the controls is press and hold the Menu button for about 10-15 seconds. That should unlock all of the controls.

It took me days of hunting through Dells website to find this when it happened to me!
http://answers.yahoo.com/question/index?qid=20060924090029AAxiOaV