Things You'll Need:
- ATX power supply tester
- Screwdriver
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Step 1
Turn the computer off. Remove all cables running from the computer, except the power cable.
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Step 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.
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Step 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.
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Step 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.
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Step 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.
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Step 6
Switch the power supply on. The tester's LEDs will indicate whether your power supply is working or has failed.









