HI! I have a G4 based macbook 17inch ~5 years old. Recently it ran all the 10.4 software updates and was running fine (did some tech work on it for a friend and it was 10.4.0 to start), it worked perfectly for 1.5 weeks but today it just went black. no power ring on the power cord slot, nothing -it is like it shorted out. Is there a reset button or a reason this could have happened? Anyone experience this? Any thoughts or ideas to try would be greatly appreciated.