How to Do It Yourself Testing ATX Power Supply

If you need to test whether the ATX power supply is in good or bad condition, the following illustration may help you.

Above are ATX power connector layout and schematic diagram guide. Now, here are steps for testing ATX Power Supply (PSU) by yourself:

1.   You can identify the Power ON pin via the only green wire goes to pin 14
2.   Using any piece of wire, short green wire with any other black wired ground pin
If the power supply has power connected and power switch on the power supply is on, you should see that the fan is turning on. Otherwise, the ATX power supply may have problem.