I got a Powerbook G4 12" from my cousin, and the hinge was all beat up. The screen wouldnt work, although it did turn on fine(fan running and HD clicking). So we took it apart, and found a broken wire in the hinge, and replaced it, and now it works. But, after using it for a while, the fan was on full blast, and wouldnt turn down. Since it was still apart, we took off the top, and the HD and heatsink were encredibly hot(i probably would have burned my finger if I kept it there long enough). I know that it will get a bit hot, but nothing should be running at that temperature. What could cause this?