Hp pavillion dv9000

Hello, I'm having the same problems as described above. The second display has been working wonderfully for a while. However, today it just didn't catch or something. Vista does recognize the second display attatched to the laptop, and so does NView. The monitor keeps doing the self test saying that everything is ok, and i can even drag off the screen as though everything was there, yet to no actually benefit. I have tried all that is listed above, I can trigger the monitor out of sleep with the [fn] + f4 combo, and off and on playing with tons of other options. I also have even tried making it my only display and, yes i loose the laptops built in, I don't gain the other monitor. Yes the monitor does work on another system. I have tried all I know and what I've read here. Any other suggestions before I have to tackle the hope that reinstalling vista will fix it? Or do you even think re-installing will give any benefit?

Thanks agian