How to Make an ATX Power Supply Work Without a Motherboard

Jump-starting a computer's power supply unit (PSU) is useful for testing component functionality without being connected to the motherboard. Even if you are not completely comfortable with the internal workings of a computer, it's a relatively easy and safe process.

Difficulty: Moderate

Instructions

Things You'll Need:

• ATX power supply
• Power cable
• Paperclip or wire

1. Find the motherboard connector. This is the largest plug coming from your PSU; it should be either 20 or 24 pins in size.

2. Bend your paperclip or wire into a U shape. You will use this in Step 4 to "trick" the PSU into thinking it's plugged into the motherboard so it turns on. If you're using a wire, make sure the ends are stripped.

3. Find the green wire. If the wires aren't colored, look for the "PS-ON" socket, socket 14 on a 20-pin connector and socket 16 on a 24-pin connector. Now find the black or "ground" wire (located next to the green wire on either side), and get ready to bridge the connection.

4. Make the connection. Insert one end of the bent paperclip or wire into the "PS-ON" socket (green wire) and the other end into the "ground" socket (black wire).

5. Plug in the PSU with the power cable and make sure the switch is turned on. The PSU should power up.

Tips & Warnings

• Although there is little chance of electric shock by using this method, keep in mind that tinkering with your computer's PSU carries certain inherent risks. Practice basic safety methods so you don't damage yourself or your computer.