How to Fix Pavilion Dv6000 Black Screen?

I have a Pavilion Dv6000 running on Windows Vista, every time i turn it on , the blue lights turn on, and it keeps rebooting itself. i have tried taking out the battery and holding the power button for 30 seconds, and then plugging in the ac power cable and turning it on but i get nothing, i have also tried pressing FN F4 too but nothing. I need a different solution, or what is wrong with it.