Need help with: Unsupported adapter installed

[oldschoolethic]

Hi. My all in one power adapter died.

I bought and tried two different power adapters, along with changing the CMOS battery but I am still getting the error:

Unsupported adapter installed 

3 long beeps and 4 short beeps

When I press the ESC key it does nothing. I have powered off the computer and turned it on multiple times along with trying different outlets. 

How can I override this?

 

[Grzwacz]

Hi,

This is a very unusual error. Have you installed any new internal hardware? Only connect a mouse and keyboard when starting the PC.

The system can't complete a POST but the CPU and RAM are detected and you have video. 

Tough to conclude the external power supply is the problem. An incompatible or bad external power supply should not yield the error you see, the PC would not start (no video and no POST error messages).

Some component connected to the MB or integrated in the MB is causing a problem. Check all RAM modules. You could have bad RAM. Or a motherboard/ CPU problem.

Try running HP Diagnostics. Start the PC, tap "ESC", select "F2".

Run system and component tests if possible.

Regards