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CT Student
Posts: 1
Member Since: ‎11-22-2008
Message 1 of 6 (71,508 Views)

Computer won't power up

My old HP Pavilion 700 desktop will not power up.  The green light on the back of the computer comes on.  I hear the fan running.  When I push the power button on the front of the computer, it starts to power up for a few seconds, then the light goes out.  The light on the back of the computer and the fan stay on.   Does anybody know what is wrong?
0 Kudos
Posts: 7
Member Since: ‎11-18-2008
Message 2 of 6 (71,488 Views)

Re: Computer won't power up

there could be a couple of things
one it could be a motherboard issue
doesnt sound like a power supply
tried unpugging everything but the monitor
than unplug the computer
press the power button for 10 seconds
plug power in and try again
Posts: 105
Member Since: ‎11-17-2008
Message 3 of 6 (71,474 Views)

Re: Computer won't power up

Desktop or notebook? You might be in the wrong forum
The First Sacred Law of Computers: Fast, Reliable, Cheap.....Pick Two The Second Sacred Law of Computers: Ask not of others that which may be easier found by Google The Third Sacred Law of Computers: Thou shalt not ask about an error message one did not bother to write down
Grad Student
Posts: 259
Member Since: ‎11-17-2008
Message 4 of 6 (71,399 Views)

Re: Computer won't power up

Possibly the motherboard, although you are in the wrong forum.


Unplug everything > Take the side off > There will be green RAM chips (Google if you don't know what these look like), press the white tabs on either side of them to pop them out > There will also be a battery similar to a nickel-sized watch battery, take it out and put it back in > Plug PC in > turn it on... Does it beep?  If yes, that means your motherboard is probably OK.  If no, your motherboard is possibly toast.  > Either way, Put the RAM back in > Try powering on again... If nothing else, try contacting HP chat support to see if they can walk you through some computer-specific things.

My posts are my opinions and experiences from working in the tech industry Smiley Happy
Posts: 61
Member Since: ‎11-25-2008
Message 5 of 6 (71,175 Views)

Troubleshooting power issues

First perform a power drain -

Disconnect everything from your computer and then hold the power button down for about ten seconds.


Flip the red voltage selector on the back of the power supply from one side to the other so it is set appropriately for your region (usually 115v in the US)


Plug the monitor and power cord directly into a known good power outlet.

Power on.

If problem remains take try using the power cord from the monitor on the computer.


If the green light on the power supply is lit up then disconnect everything and hold the power button down again, then open up the case and reseat the main power connector which has about 20 red, black, and white wires coming out of it and a white plastic connector on the end. If there is a four wire connector with black, white and yellow wires coming from it then reseat that as well. 


You will also want to reseat the wire that goes from the power switch on the front of the case to the motherboard. it is usually a thin green and white wire.


 Still not working? Then you will want to disconnect the power connectors from all the devices and try it. There will be a connector with red, yellow, black, and white on the back of each device such as the hard drive and DVD drive. By disconnecting the power from these devices you can ensure one of them does not have a short or fault.


Most of the time the problem is simply the power supply. If you recently had a power surge or outage then your are probably out of luck. Power supplies are usually fairly cheap and easy to replace though so as long as your motherboard is still in good shape you should be fine.


In this particular case the computer stays on for a few seconds and/or shows the HP/Compaq logo you may want to try entering the BIOS using F1 for XP and F10 for Vista. If it stays in the BIOS with no problem then their is most likely a SW issue and a recovery maybe the best option for a quick fix.


Good luck Man Very Happy

Posts: 1
Member Since: ‎08-12-2009
Message 6 of 6 (68,005 Views)

Re: Computer won't power up

I had the same thing happen on my HP pavillion a350n.  All I did was open the case took out the Ram and put the Ram back in and it now powers up just fine Smiley Happy.
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