One of my computers turned itself off, and nothing happens when I press the power button. So I tried to come up with a list of possible problems:
1. No AC wall power
2. Dead power supply
3. The motherboard circuitry that tells the power supply to turn on has died.
4. Power button is broken or not connected to the motherboard.
5. Power supply refuses to start because of a short circuit.
I unplugged the power cord from the power supply and used a multimeter to verify that there was power, ruling out possibility 1. I then plugged the cord back in and disconnected the 24 pin power connector from the motherboard. The multimeter confirmed that the power supply was producing 5 volt standby power. I then used a staple to connect PS_ON (green wire) to ground (black wire), and the power supply turned on, so I think the power supply is fine.
That leaves possibilities 3 through 5. I guess the next step is to disassemble the computer and see if the motherboard can turn on the power supply when out of the case.
In any case, I'm posting this here because if my list of possibilities is complete it might be helpful to someone else, and if it's not complete having someone point that out might be helpful to me.
1. No AC wall power
2. Dead power supply
3. The motherboard circuitry that tells the power supply to turn on has died.
4. Power button is broken or not connected to the motherboard.
5. Power supply refuses to start because of a short circuit.
I unplugged the power cord from the power supply and used a multimeter to verify that there was power, ruling out possibility 1. I then plugged the cord back in and disconnected the 24 pin power connector from the motherboard. The multimeter confirmed that the power supply was producing 5 volt standby power. I then used a staple to connect PS_ON (green wire) to ground (black wire), and the power supply turned on, so I think the power supply is fine.
That leaves possibilities 3 through 5. I guess the next step is to disassemble the computer and see if the motherboard can turn on the power supply when out of the case.
In any case, I'm posting this here because if my list of possibilities is complete it might be helpful to someone else, and if it's not complete having someone point that out might be helpful to me.