I receintly picked up 14 G4/400 Gigabit-Ethernet computers for 5 bux each.
About half of them seem to have dead power supplies. Anywho, since people
are buying these things DEAD on ebay, I imagine that it's an easy fix to do.
After disecting several supplies and repairing two due to burned resistors
and one capacitor, I am stumped with the remaining problems. Someone HAS to
know what goes bad on these things. I did discover that leaving the
Gigabit-Ethernet and Digital Audio G4s plugged in and NOT turned on will
kill the power supplies (thanks Apple). Seems that the 28 volt line is
being used by the motherboard when the computer isn't really on. The
problem is that the power supply fan isn't on when the computer is off so
the circuit board in the power supply cooks from the heat. Either unplug
those G4s from the wall *OR* leave em on sleeping. Try this sometime, turn
ON a Gigabit or Digital Audio G4 sometime when it's been off for a while and
feel the temperature of the air leaving the power supply. It's pretty darn
warm for the computer being off.
Anywho, someone HAS to know what goes bad on these things.