electricli 0 Newbie Poster

I have a HP Pavillion zv5330us with a 15.4" LCD. ONe day, the display just goes dark as if the backlight went out. I connect it to an external monitor, and the display comes back on, bright as day. Then it went on standby, and stayed dark. Every once in awhile when I connect it to an external monitor it will come back one. Any suggestions? :o :o :o :o