HP Compaq 4000 Pro <HELP>

[lbwlow]

Greetings people
I got a HP Compaq 4000 Pro SFF desktop that won't power up (not to say it totally won't), bought it from a junker though. With or without RAM, diagnostic LED indication will blinked red for 2 times (1 blink for every second followed by 2 second pause), same as the beep code. It power up as soon as I switch on the mains, both CPU and PSU fan spins for just 1 or 2 seconds and stop spinning after that, and the beep and blink codes continues.

I tested the CPU, RAM and HDD on other PC and it all works.

Here a video to my blink code:
https://www.youtube.com/watch?v=1pZD...ature=youtu.be

I refer my blink code to HP's service manual and I don't find a match.
But if I disconnect 4 pin CPU power connector, I get a different blink code, 4 blinks, 1 blink every second followed by a 2 second pause. And there a match, according to the service manual it is power failure, power supply overload.



This was a proprietary HP PSU, with 6 pin, another smaller 6 pin and 4 pin CPU power connector. I jumped started the PSU by shorting green to black wire, the PSU does power up and the fan is running at full speed. Wasn't sure if this is how it behaves though, I have non of a experience dealing with HP SFF system.




In this board have some KZGs though, wasn't sure they are bad, they all looks good, no bungs, leaks or bloat.

Can anyone please share with me with any experience with HP SSF system? And help identify the unknown blink code that is not listed in the documentation. Any help is appreciated

[stj]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

maybe there is a short on one of the power lines.

[Mad_Professor]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

Was there a fan for the processor heatsink? you might need to connect a fan to one of the headers on the motherboard before it will power on.

Also you need to connect the P4 connector, googling image search shows for the 4000 that it is connected, and went away on 6xxx and 8xxx series.

[lbwlow]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

maybe there is a short on one of the power lines.

Hmm, can u elaborate more on which power line to be specific?

Was there a fan for the processor heatsink? you might need to connect a fan to one of the headers on the motherboard before it will power on.

Yup, there is, it has a air duct, I removed it to snap some pics, similar to dell BTX design.

[Mad_Professor]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

If I had to guess based on other information, like this

http://h20564.www2.hp.com/hpsc/doc/p...ts.oid=3658084

and this

http://h20564.www2.hp.com/hpsc/doc/p...r_na-c00274415

and here

http://h20564.www2.hp.com/hpsc/doc/p...mmr_kc-0100459

It's a recurring theme.
I would say either the cpu fan is not sending a PWM signal to the board and the board is going into protection mode to prevent damage or someone has flash the wrong bios on to that board.

It's unusual especially on a business class workstation to have undocumented diagnostic code, unless hp compaq add it to a bios update after release.

[lbwlow]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

If I had to guess based on other information, like this

http://h20564.www2.hp.com/hpsc/doc/p...ts.oid=3658084

and this

http://h20564.www2.hp.com/hpsc/doc/p...r_na-c00274415

and here

http://h20564.www2.hp.com/hpsc/doc/p...mmr_kc-0100459

It's a recurring theme.
I would say either the cpu fan is not sending a PWM signal to the board and the board is going into protection mode to prevent damage or someone has flash the wrong bios on to that board.

It's unusual especially on a business class workstation to have undocumented diagnostic code, unless hp compaq add it to a bios update after release.

Thanks for the info
If it was the fan not sending PWM signal is there anyway that i can bypass it ? I did remove the board from its casing and attempt to power up the board with a stock intel HSF sitting on top for testing and use a slight force to connect the stock intel fan power connector to HP's connector, and it still the same.

[Mad_Professor]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

Thanks for the info
If it was the fan not sending PWM signal is there anyway that i can bypass it ? I did remove the board from its casing and attempt to power up the board with a stock intel HSF sitting on top for testing and use a slight force to connect the stock intel fan power connector to HP's connector, and it still the same.

Use another PWM fan, which sounds like you did. You can measure voltage from the PWM wire usually between 1 to 3.3v, I tend to use a thin sewing pin and the alligator clip leads on my DMM. Ground one to the case and attach the other to the sewing pin, I usually insert the sewing pin first then attach, and ensure it doesn't come in contact with anything nearby that could potentially short it and cook it.

You could remove PWM wire from the connector, it's usually held in with a friction clip, lifting it and removing the wire will do it, using a simple DC voltage Fan will do the same trick. It's possible that it's not sensing RPM and throwing the error code.

You can also swap processors, since thermal shutdown is caused by a sensor either on the board or from internal sensors on the processor. So if you have another lga775 chip, give that a try.

[Mad_Professor]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

Thanks for the info
If it was the fan not sending PWM signal is there anyway that i can bypass it ? I did remove the board from its casing and attempt to power up the board with a stock intel HSF sitting on top for testing and use a slight force to connect the stock intel fan power connector to HP's connector, and it still the same.

EDIT:
ummmm what the shit? duplicate after editing?


Use another PWM fan, which sounds like you did. You can measure voltage from the PWM wire usually between 1 to 3.3v, I tend to use a thin sewing pin and the alligator clip leads on my DMM. Ground one to the case and attach the other to the sewing pin, I usually insert the sewing pin first then attach, and ensure it doesn't come in contact with anything nearby that could intentionally short it and cook it.

You can also swap processors, since thermal shutdown is caused by a sensor either on the board or from internal sensors on the processor. So if you have another lga775 chip, give that a try.

[lbwlow]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

Use another PWM fan, which sounds like you did. You can measure voltage from the PWM wire usually between 1 to 3.3v, I tend to use a thin sewing pin and the alligator clip leads on my DMM. Ground one to the case and attach the other to the sewing pin, I usually insert the sewing pin first then attach, and ensure it doesn't come in contact with anything nearby that could potentially short it and cook it.

You could remove PWM wire from the connector, it's usually held in with a friction clip, lifting it and removing the wire will do it, using a simple DC voltage Fan will do the same trick. It's possible that it's not sensing RPM and throwing the error code.

You can also swap processors, since thermal shutdown is caused by a sensor either on the board or from internal sensors on the processor. So if you have another lga775 chip, give that a try.

Okay, thanks for the tip
Will try it tomorrow and report back on how it goes.
I already swap the processor, from the original e5800 that comes with it to e2200, and it still the same

[stj]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

did you test the psu on another system?

[lbwlow]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

I can't test it, because I don't have other system available that share similar PSU.

[stj]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

well you said "if I disconnect 4 pin CPU power connector, I get a different blink code, 4 blinks, 1 blink every second followed by a 2 second pause. And there a match, according to the service manual it is power failure, power supply overload"
that makes me think the psu has a problem, or the cpu connector has something shorted causing the psu to shutdown.

the fans are the giveaway.

[lbwlow]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

I tested the stock PWM fan wire and it give me voltage output of 1.3-1.5V. If it was because of a faulty CPU temp sensor on the motherboard is there anyway that I can bypass it ?

well you said "if I disconnect 4 pin CPU power connector, I get a different blink code, 4 blinks, 1 blink every second followed by a 2 second pause. And there a match, according to the service manual it is power failure, power supply overload"
that makes me think the psu has a problem, or the cpu connector has something shorted causing the psu to shutdown.

the fans are the giveaway.

I open the PSU and do some simple test using DMM today, and I found a diode seems to be bad, tested using diode mode on my DMM, on forward voltage i got 0.318V, but when tested in reverse, I got a reading that rise from 0v until it says OL. It was tested in circuit though.

[stj]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

that reading is probably o.k., your seeing a capacitor discharge.

[lbwlow]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

U were right, I removed the diode off circuit for testing and it is working as it should.

Now i figured something weird, when older LGA775 processor is inserted for testing, what i tested is Celeron D and Pentium 4 506, the LAN port LED would light up when I power on the system, it doesn't always light up, sometime it would, sometime it wouldn't. With those processor in, the CPU and PSU fan won't switch off this time, and there is no beep code. But the processor barely warm up at all.
What does the LAN port LED that lighting up indicate?

[stj]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

i think it means the lan chip is getting power AND detecting an active connection.

[saeedkhan]

Can u provide Me BIOS of that system.

[kaboom]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

Recap the power supply. It's full of crapxons, teapos, and ltecs.


Those systems acted real strange once the caps started going- you then had the MB caps attempting what the ones in the PS should've been doing.

You may have to recap the MB anyway, if it's got KZGs/KZJs...

[lbwlow]

Re: HP Compaq 4000 Pro &lt;HELP&gt;

Okay, I will desolder a couple caps off the PSU and do capacitance measurement and see how it goes