This could be a ram problem try removing ram one dimm at a time and trying it 1 at a time in each dimm slot. there could be one bad stick of mem or one bad dimm slot so by trying each dim stick in each slot you can eliminate the possibilitys. A static discharge is also an option . Unplug the machine and pull the battery then hold down the power button for a full 60 seconds then release and do it again then put the battery back in plug in the laptop and try to reboot. If these dont help try connecting to another monitor to see if its a video screen problem. after that whats left is probably a GPU problem.