4 Beeps and Red LED Upon Powering HP Compaq dc7900 Desktop

[UWW]

Hello,

I'm currently working on an Hp Compaq dc7900 Base Model Ultra-slim Desktop PC. Upon attempting to power on the desktop, the LED light blinks red and beeps 4 times. Most forum posts I read regrading the issue have said it's a power supply issues. I've tried several different external power supplies all with the same result. I can't boot the computer to get into the OS or BIOS. If anyone has any idea what the issue could be I would appreicate any suggestions.

Thanks. 

[TheOldMan]

HERE IS THE TROUBLESHOOTING MANUAL for that PC.  On page 58 - Table A-2 indicates the

    Red Power LED flashes four times, once every second, followed by a two second pause. Beeps stop after fifth

   iteration but LEDs continue until problem is solved.

 It then continues on with the possible reason as an overloaded power supply.  Read the rest of the explanation, also.  Disconnect all external devices to see if any of those items are causing the problem, (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.

Read the rest of the possible solutions if the problem has not been resolved

[UWW]

I'll read the suggested material over now and give that a try. I will report back with results soon, thanks for the suggestion. 

[Fazeehmf7]

Did you get any results?

[kevin-t]

Hello,

Thank you for posting in this thread. Unfortunately based on when the last response was made, I have closed this thread to help keep comments current and up to date. We recommend starting a new thread for your issue. 
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Thank you

[User2006]

I Have this problem and I have tried helping the power supply by unplugging my mouse and keyboard and I made sure nothing else was either but this problem still exists, I can sometimes if I wait a day or two get it to work for about 30 minutes any ideas what the problem can be?