I have been reading for two days and not seen this particular problem or a solution. I have a Compaq Presario V3000 laptop that is about 3 years old. The keyboard keys were acting sluggish so I opened it up and removed the keyboard to clean it. I put it back together and now it will turn on, but the screen is black. I cannot start in safe mode or from my windows xp disk. I have tried f7, f9, and f11. Nothing. I have also reseated the memory cards. Any ideas?