HP Pavilion 7915

Pavilion 7915 after a few reboots and running for a few days with no problems, the pc was shut down. I’ve restart the pc and the hard drives spin up, the cd-rom starts up but there is no video. All the lights on the keyboard(num,caps,scroll lock) are lite, but now the pc wont boot, i get no post scrren nor any beeps.
Anyone got an idea?