How to Test an ATX Power Supply

Testing your power supply is vital in the process of diagnosing hardware and logical failures in your computer. A failing power supply can cause any part of your system to fail, so the power supply should be tested early on in the diagnosis process.

Things You'll Need

• ATX power supply tester
• Screwdriver

Instructions

1. Turn the computer off. Remove all cables running from the computer, except the power cable.

2. Remove the screws that are securing the side panel of the case; they're located at the back of the computer. Slide the side panel of the case off of the computer's frame.

3. Locate the power supply inside the case. Follow the thickest mesh of cords running from the power supply to the motherboard; it will be plugged into a wide port on the motherboard.

4. Take a firm hold on the power port with the thumb and forefinger of one hand, and use the other hand to remove the cable from the port.

5. Plug the power supply's cable into the power supply tester. ATX power supplies come in two types: 24-pin and 20-pin. In either case, match the squared bottoms of the cable's micro ports to those of the tester's, aligning the ports to the left of the tester.

6. Switch the power supply on. The tester's LEDs will indicate whether your power supply is working or has failed.

Resources

• ATX Power Supply Tester