i have an hp d series laptop it was fine one day then later that day i tried to get on it i put my pass word in and then my screen turned black so i powered down and it did the same so i took the battery out and i turn it on the fans and everything starts running the screen stays black then about 15 to 20 seconds later it shuts right off what could be wrong because if i could fix it my self i would instead of taking it to get fixed