test power supply with multimeter

[coolnametaken]

Does anyone know how to use a multimeter to test a 250W PC power supply to ensure it is supplying the right amount of voltage/amperage?

 

[ttn1]

Basically all you have to do is connect the ground probe to a ground wire on the power supply, always
a black wire. Then probe the other points on the connector for voltages.

Just be careful not to short out any connections.

This is easy for an old AT power supply as you can turn it on easily without a motherboard connected.
ATX power supplies make it a little more difficult to turn on without a motherboard connected. I can't
remember the pinouts off hand, so I can tell you which pins to short to get an ATX to turn on.

You can probe the ATX connector from behind while connected to the motherboard, just be careful not
to short anything out.