Have Dell Inspiron laptop running Win XP Home.
The LCD screen goes blank every once in a while.
However if the screen is touched with a finger it comes up
again. Also, if a monitor is attached to the VGA port the
external monitor works just fine. It's definably
not a battery issue and video card seems fine too since
external monitor works fine.

Do I have busted LCD screen or are there some other
things I can try to revive it?
thanx

Sounds like either the backlight is on its way out or there is a loose
connection. Based on what you've said, loose connection is more likely. If
you're adventurous you can open it up and take a look.

mac