when i got back my computer i noticed that the red and green light on the bottom of the computer were not comming on so i called the technitian and he said that my machine got hit probably by low voltage or overload and that is why it crashed so probably the power supply got damaged and that is probably why the lights are not comming on. if my memory serves me right i think they were working before i gave it to him and the machine is now not picking up one of the memory stick