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cpu not booting after power supply replacement

dc5700.small form factor
Microsoft Windows 7 (32-bit)
I recently replaced the power supply model AP15PC56 after it blew up with part number 404472-001. now the cpu won't boot up. when I connect to power it makes 4 short beebs and the indicator lights red. what could be wrong?
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cpu not booting after power supply replacement



Please refer to this HP Support document for all troubleshooting tips.


The failed power supply may have fried the motherboard.


Here is an excerpt from this document that appears to describe the symptoms you are experiencing:


Power LED flashes Red four times, once every second, followed by a two second pause, and the computer beeps four times. (Beeps stop after fifth iteration but LEDs continue flashing.)
Power failure (power supply is overloaded).
  1. Check that the voltage selector, located on the rear of the power supply (some models), is set to the appropriate voltage. Proper voltage setting depends on your region.

  2. Open the hood and ensure the 4- or 6-wire power supply cable is seated into the connector on the system board.

  3. Check if a device is causing the problem by removing ALL attached devices (such as hard, diskette, or optical drives, and expansion cards). Power on the system. If the system enters the POST, then power off and replace one device at a time and repeat this procedure until failure occurs. Replace the device that is causing the failure. Continue adding devices one at a time to ensure all devices are functioning properly.

  4. Replace the power supply.

  5. Replace the system board.

† The opinions expressed above are the personal opinions of the authors, not of HP. By using this site, you accept the Terms of Use and Rules of Participation