HOW-TO: ATX Benchtop Power Supply

You Will Need:

  • An old ATX computer power supply
  • Some binding posts
  • A switch
  • Standard modder tools

Prepping the PSU

Open the power supply’s case and remove the fan. Locate the wires that are needed. For a standard power supply, these will be Yellow: +12v Red: +5v Black: Ground Blue: -12v White: -5v Orange: +3.3v Green: Short to Ground using an SPST Switch for Power-on. Brown or Lighter Gauge orange: 3.3v Remote sensing. Check for an extra wire connected to Pin 11 on the P1 connector. If you have one, this wire needs to be connected to the 3.3v rail. Clip all the other wires at the circuit board level.

Prepping the Case

Get some binding posts. These can be had from RadioShack or any other electronics supplier. Drill some holes for these on the front of the case, above where the fan used to be. Also drill a hole for a switch. Mount your binding posts and switch. Check for shorts between each binding post and the case with an ohmmeter.


Solder a wire from each voltage you want to use to a binding post. Solder the green wire to the switch along with a ground wire.

Packing up

Stuff all the wires in the case. Run the fan wires out of the hole where the wires used to be and attach it to the top of the case. Make sure it blows air downwards onto the PSU.

You’re Finished!

That’s it! Just plug it in, flip the master switch (if you have one), and hit the power switch. You have a new benchtop power supply!

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