PowerBook g4 has startup chime no image
My powerbook g4 15" 133mhz 1gb ram 120 gb hard drive starts with the startup chime but gets no screen image. Screen does become lit up. So it looks like display has power. I hear the dvd drive at startup but don't hear the hard drive spin up. Hooking up an external monitor produces no image. I bought the machine on ebay about a year ago. It came with system 10.5.8 but I don't have the discs to re-install. I do have 10.4.11. Is it the hard drive. I have another and could replace. Or is it the logic board, probably not worth fixing. Thanks.