Desktop won't start; blinking green light

[LSvach]

I have a Compaq Presario SR 1318NX which will not start!?  There is a blinking green light on the back of the power supply; which is normally solid green when 110V AC is plugged into it.  I have tried the trick of holding the start button while plugging in the power cord ..... no help.  I have also opened the case and carefully removed every power cord to all the internal devices ................ the light turns solid green only when I pull the main power from the motherboard!

 Do I need to replace the motherboard?  The troubleshooting site on hp.com would indicate the power supply is OK if the light is solid green.

Thanks for any suggestions,

Lou

[RasterBlaster]

Maybe this document will help if you haven't already used it:

Troubleshooting Power Supply Issues

[c0rnel]

If it's blinking green than msot likely the power supply needs to be changed.

Also check the 24volt cable going to the motherboard by opening the pc case and reseatting that cable.

[LSvach]

Thanks, RasterBlaster and cOrnel,

Yes, I have tried the troubleshooting hints on Hewlett Packard's website and all I can find is that the blinking only occurs when I connect the big 24-pin connector to the motherboard!?  I think that isolates it to the motherboard?

H-P doesn't seem to carry a replacement motherboard for this computer; any recommendations on a replacement?

Thanks,

Lou

[RasterBlaster]

Things I would try (you may have already done these):

You may have a 12V ATX line (6 wires) that needs to be connected to the mobo in addition to the main power (about 20 wires). Make sure they are both connected - try again.  

Remove 1 stick of memory - try again.

Swap the stick you removed with the other stick and try again.

Unplug the power switch wires from the header on the mobo - try again - make sure you write down where each wire goes. Try again.

Swap the power supply with another ATX to see if it is the power supply (PS fail more than mobos due to dust buildup).

[skullbucket]

Just had the same problem. Looked at the troubleshooting guide and nothing worked. Accidentally unplugged the main motherboard power while the PC power was still plugged into the outlet and then plugged back in and presto, now it works.

[paulmar · Accepted solution]

My wife's computer has been having the same problem several times. One solution I found that worked before was to unplug the motherboard power cable and the PSU power cable from the back of the PC and then connect the power cable and connect the motherboard power cable while holding down the power button. Scary, to say the least, but it worked, until one day I accidentally flipped the wrong breaker and then spend two hours trying the same solution with no luck and Googling again. And here is what I found. This is the simplest yet crudest solution. It’s easy and non invasive and it doesn’t matter how tech savvy you are. Take a blow dryer and turn it on to blow air at the back of the power supply for a couple minutes. When you see the light turn green you’re all set. It's worked for me after it worked for a hundred others, maybe more. See the testimonials on this site: http://talk19.wordpress.com/2008/01/13/hp-m7088d-power-supply-led-blinks-green/. It’s a shame that nothing like this appears on any HP site. So don’t waste your money on a new MoBo or PSU. All you need is your wife’s hair drier.

[Suebcee]

The hairdryer trick totally worked!  Just to explain further...  Have all your stuff connected to the machine first (keyboard, mouse, monitor)!  I DID NOT and I was in a panic because I had to shut if off and turn it on again to get the devices to work!  I was sweatin' that out!  Have the hairdryer on hot, hold it away from the psu fan a bit, don't want to cook it.  Took about 40 seconds for the light to burn a steady green.  Hit the power button & voila!  Don't know how long it'll last, but my daughter's computer is on for now!  When she's happy, we're happy!    Thanks for the tip!!!

[anwarmian]

To my amazement the hair dryer trick worked for me.  I cannot believe my eyes.  I plugged a different power cord into the supply and the green light was blinking while I was blowing the hair dryer.  Everything was connected during this process.  I blew the dryer for minute and a half then the geen light became steady and I was able to turn the computer on normally.  However, when I unplugged the power cord and replugged the original it started blinking again so I once agian  blew dryed it.  This time it took less than a minute for the green light to become steady and I was able turn on the computer again.   Thanks to God and thanks to you guys.:smileysurprised:

[cambuslang]

Why does this work? I just spent hours last night and this morning trying to fix this issue. Found this on a link, so Happy Thanksgiving 2011

William

My wife's computer has been having the same problem several times. One solution I found that worked before was to unplug the motherboard power cable and the PSU (power supply unit)  power cable from the back of the PC and then connect the power cable and connect the motherboard power cable while holding down the power button. Scary, to say the least, but it worked, until one day I accidentally flipped the wrong breaker and then spend two hours trying the same solution with no luck and Googling again. And here is what I found. This is the simplest yet crudest solution. It’s easy and non invasive and it doesn’t matter how tech savvy you are. Take a blow dryer and turn it on to blow air at the back of the power supply for a couple minutes. When you see the light turn green you’re all set. It's worked for me after it worked for a hundred others, maybe more. See the testimonials on this site: http://talk19.wordpress.com/2008/01/13/hp-m7088d-power-supply-led-blinks-green/. It’s a shame that nothing like this appears on any HP site. So don’t waste your money on a new Motherboard or PSU. All you need is your wife’s hair drier.