원문 게시자: lemerise ,
There's a documented issue for the iBook G4 who has the fellowing symptoms at boot up: no chime, screen stays black, fan runs full speed, no other activity. This problem is often related to a IC power regulator named U28 and located near the DC in board cable socket under the iBook G4 logic board. The IC power regulator has 40 pins but only the pins 1 and 21 can be desoldered from the logic board and causing a power issue at boot up. Just briefly applying a fine tip from an iron solder gun to the two pins to resolder them can restore the IC communication with the logic board. A Google search would give you more info about the U28 issue.