HP desktop gives me red light and beeps on power

[DVINTHEHOUSEMAN]

So I have a dc7100 SFF with a P4 in it. I put a Pentium D 820 2.8GHz in the socket and it gives me 9 beeps, each a second apart and it gives me a blinking red light on power. When I put the P4 back in it works. Why is this?

[wb2001]

@DVINTHEHOUSEMAN 

It is a less than $4.00 fix. You need a NEW coin battery. That should reset the CMOS.

http://www.fixya.com/support/t13948704-system_not_fetching_code

[Paul_Tikkanen · Accepted solution]

Hi, @DVINTHEHOUSEMAN 

The answer to that question is simple.

The dc7100 does not support any Pentium D processors.

You need a dc7600 to run one of those.

Below is the link to the dc7100 quickspecs.

The supported processors can be found on page 5.

https://www.nts.nl/site/html/modules/pdf/PC/dc_7100.pdf

I would not go beyond the P4 650 because the faster ones require much more wattage and will generate way too much heat for the cooling system to process.

And as for interpreting the the beep codes for the dc7xxx model series, please refer to the troubleshooting guide at the link below, starting on page A-14...

http://h10032.www1.hp.com/ctg/Manual/c00189283

[DVINTHEHOUSEMAN]

Okay. I will just use the P4. I used to have a 7600 but the power supply blew 🙁

[Paul_Tikkanen]

You can probably use the P/S from the dc7100 in the dc7600 if it is the SFF model.