1.MOST COMMON PROBLEM WITH POWER SUPPLY.
a.Power supply fails and needs to be replaced.
b.Power supply is switched to the wrong voltage. Should be 115V instead of 230V.
c.When testing or installing a new power supply, the supply is plugged directly into the motherboard without plugging another device such as a floppy drive. The power supply may short out if it is plugged only into the motherboard.

2.Hear whining noise from the computer.
a.Most noise related problems originate from the power supply or fan.
b.Could be ball bearings in the fan not turning properly.
c.Could be a noisy hard drive.

3.System restarts intermittently.
a.Check that the switch on the power supply is switched to the 115V position and not 230V.
b.Could be bad power supply.

4.No Power.
a.Check that power cord to computer (printer) has not become unplugged.
b.Plug another device into surge protector or outlet. Check that the surge or outlet providing power.
c.Try a different outlet.
d.Try the same power cord on another device. Cord may be bad.

5.Computer seems to cause interference with radio / TV.
a.Computer casing may not be FCC certified.
b.Power supply may be causing problem. Try re-orienting the computer or move to another room.

6.Turned on power supply  to test it and the power supply shorted out.
a.Something other than the power cord must be plugged into the power supply or the power supply will short out.
b. Plug in a floppy, CD or motherboard.