Computer does not power on when power button press. However, green light on back blinks on and off.

[Audioicon]

Good evening everyone!

I currently own an HP A564n Pavillion Desktop.

My computer stop powering on but the light on the back of the unit by the power suply  blinks on and off.

I'm wondering if this is a power suply problem or a problem with the main circuit board.

Has anyone ever experience this problem before?

The computer does not come on when you press the power button.

The power button is not broken.

However, when you turn on the power, nothing comes on, just the green power supply light comes on and off.

Any help or ideas?

Thanks everyone.

Audioicon

[TheOldMan]

It could be either one.  I found this discussion on a similar problem but an older version of the hardware.  Here is a suggestion from that thread

"I have a 8667c pavilion desktop and here 's what I got from HP.
My machine can fail to boot as there is a build-up charge on the motherboard.
The workaround is to hold in the power button for 5-10 minutes while the power cable is disconnected (I prop it "ON" with a stick).
After 5-10 minutes, it boots-up fine"

If that doesn't do you any good, the first thing I would do is replace the power supply (unless you have a PS tester that can verify the PS).  That is most likely the cheapest fix.  Or you can open the case and verify everything is still connected properly but you can do that in the process of replacing the PS.

[Audioicon]

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@TheOldMan wrote:

It could be either one.  I found this discussion on a similar problem but an older version of the hardware.  Here is a suggestion from that thread

"I have a 8667c pavilion desktop and here 's what I got from HP.
My machine can fail to boot as there is a build-up charge on the motherboard.
The workaround is to hold in the power button for 5-10 minutes while the power cable is disconnected (I prop it "ON" with a stick).
After 5-10 minutes, it boots-up fine"

If that doesn't do you any good, the first thing I would do is replace the power supply (unless you have a PS tester that can verify the PS).  That is most likely the cheapest fix.  Or you can open the case and verify everything is still connected properly but you can do that in the process of replacing the PS.

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Thanks very much for the reply! I really appreciate your time and efforts. 🙂

Unfortunately, my issues are different. There is no power! The computer does not turn on at all.

However, there is a green light on the back of the power supply that is suppose to come on when you press the power button, this light is suppose to remain solid green!

Right now the light blinks with a clicking noise but the power button does not light up and the computer does not boot.

What I have done so far.

I unplugged the wires from the power supply  that connects to the Motherboard and the green light on the power supply stopped blinking and stayed on solid. However, when I attached the wires back to the Motherboard, the light starts to blink with the clicking noise. This noise is coming from the light.

I also removed the graphics card, PCI card, RAM and disconnected the hard drive but the problems continued.

The only time the light does not blink is when I unplug the wires from the power supply to the Motherboard.

I read a documentation on the HP website that explains this problem and according to the notes - the problem is the motherboard.

According to the documentation - if you unplug the Motherboard and the light continues to blink, then the mother board is not the problem.

If the light stops blinking after you unplug the mother board, then the mother board is the problem.

I will post a link to this documentation.

Thanks - Audioicon

[mikeplaga]

I have a HPm1170 that is doing the same thing. How ever mine is set in the BIOS to power up when AC power is restored.

If I unplug the power supply from the mother board the light comes on solid. when I plug it back in the PC will boot up normally and run all day. I tried shutting it down for a few minutes and then restarting it and it works fine.

After sitting all night I have the same problem.

I wonder if the voltage from the power supply that powers the board when it is off is too low and not allowing the power button to work. Try holding the power button while plugging the power supply into the board. The voltage may be high enough before you plug it in to trigger the PC to start.

[1Elkman]

Audiocon - I have the same symptoms on a Pavilion a350n. It is the motherboard. "Hotplugging" in the 20pin cable will fix the problem until the ac power is interrupted. I am lookin for information on which IC is bad on another thread. My motherboard is a P4SD-LA. If you still have issue after hotplug workaround - change the Li-battery.

[maverickse34]

Hello I know this post is old but I'm having the same problem with my hp, it was given to me by my mother-inlaw and was working fine the day she gave it to me, she unplugged it boxed it up and I picked it up took it to my house and put it together and plugged it in and the green light on the psu started blinking! (i think she didn't power it down correctly) anyway I did some research on these forums and Google and found everyone who has had the same problem has fixed it with hot plugging the power to the motherboard but its not working for me! I unplug the power to the mobo and the light stops blinking, then I unplug the cord from the wall and wait awhile then plug the cord back into the wall the light comes on solid and then I plug the power to the mobo back in and the light starts blinking again! Any suggestions please?

[wb2001]

The standard test link is here:http://support.hp.com/us-en/document/bph06788

[reckoffp]

I have the exact same issue as you had.  Did you ever find out the solution, other than hotplugging power to the motherboard everytime you lose power?

[northernbell]

Where can I buy a new power supply that's reasonable

[northernbell]

I seen a clip on utube. es how to change it