Pavilion desktop won't turn on - getting a series of three beeps

[Nick012345]

When I turn on the Pavilion I'm hearing a series of three beeps and then getting a message that an supported adaptor is installed and the computer will be powering down automatically soon.  Any ideas how to resolve this?  Thanks

[Echo_Lake]

@Nick012345
Thank you for posting on the HP Support Community.

I have a few troubleshooting steps we could try to fix the issue:  

1. Disconnect everything from the computer, including the power cord.

2. With the power cord disconnected, press the power button on the front of the computer.

3. Plug in the power cord to see if the computer automatically turns on.
   And, also refer to the Article "Computer Does Not Start and Emits an LED or Beep Code"

Hope this helps! Keep me posted for further assistance.
Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.