powerbook g4, dead screen and beeps
The three beeps is an indication that for some reason it's not been able to successfully pass the RAM check part of the POST, or a bit more seriously that the logic board is dead. First step is to open it up, pull the RAM and boot it, if it makes one beep then it's the RAM so reseat it and see if it works. If it makes three beeps again, then it's a new logic board.