I had the same problem. I have an HP Pavilion DV9700. It's a decent machine, when it works. Two hard drives, nice screen - it seemed like a good choice at the time. But I was using it one evening working on a very important paper for work when the screen got all distorted. I couldn't move the mouse or anything. I unplugged it thinking maybe it just needed to cool down because it always ran hot. A few minutes later I plugged it back in, and the screen wouldn't come up at all.
Luckily I had my desktop as a backup, so I was still able to get my work done! I found a place in Florida called Precision Division. They specialize in circuit-level laptop motherboard repair. I sent them an email, telling them about my DV9700 and they told me that it was something they fixed on a daily basis. The explained the procedure. I didn't really understand the technical terms but it sounded good. Anyway I shipped the beast off - and they were able to fix it. They made some improvements to the laptop so that it would last longer. My laptop now has two fans! The only problem with that is that it drains the battery faster but I hardly ever run it on battery. They told me that it's best to leave the battery out while I'm at home, because it will help the laptop stay cooler and reduce wear and tear on the battery but I'm lazy and don't like to remove it if I don't have to. It's been a few months now since I got this thing fixed and it's still going strong. I'm trying to get in on that class action lawsuit against HP but I think it might be a little late. No big deal but it would be nice if they reimbursed me for my repair. If this notebook ever goes I'm not sure what I'd buy, HP isn't "terrible" but I was told that Toshiba makes some really dependable laptops.