Jump to content


Register a free account to unlock additional features at BleepingComputer.com
Welcome to BleepingComputer, a free community where people like yourself come together to discuss and learn how to use their computers. Using the site is easy and fun. As a guest, you can browse and view the various discussions in the forums, but can not create a new topic or reply to an existing one unless you are logged in. Other benefits of registering an account are subscribing to topics and forums, creating a blog, and having no ads shown anywhere on the site.

Click here to Register a free account now! or read our Welcome Guide to learn how to use this site.


My Computer Won't Turn On!

  • Please log in to reply
5 replies to this topic

#1 jhalldmw


  • Members
  • 3 posts
  • Local time:09:10 PM

Posted 31 May 2008 - 02:13 PM

whenever i push the power button instead of turning on the only thing that will happen is my fan led will flash for a split second and then nothing regardless of how many times i push the power button. The only way I can get my computer to show any sign of life is to turn off the power supply for a few seconds and then turn it back on, then when I push the power button the fan LED will flash again. Eventually if i have the patience to go through this cycle several times it will eventually (if i'm lucky) turn on. Any advice or help will be greatly appreciated.

BC AdBot (Login to Remove)


#2 hamluis



  • Moderator
  • 56,562 posts
  • Gender:Male
  • Location:Killeen, TX
  • Local time:07:10 PM

Posted 31 May 2008 - 02:25 PM

I think I'd install a different power supply (at least temporarily) to see what occurs.


#3 sweeney.172


  • Members
  • 12 posts
  • Local time:09:10 PM

Posted 31 May 2008 - 04:16 PM

I want to start this reply with a small disclaimer. I'm not a computer expert...

I have been having symptoms similar to that recently. I will come into the room only to find that my computer has frozen and will not respond at all. After holding the power button to shut down (does that count as a hard shutdown?) the computer won't turn on again for a while. I'm suspecting the computer is getting too hot and to prevent damage, it's automatically shutting down, just not correctly. I think after the internals have cooled down, it will power back up again. Now I want to repeat, I'm no expert. But this is what I'm leaning towards in my diagnosis.

#4 garmanma


    Computer Masochist

  • Members
  • 27,809 posts
  • Gender:Male
  • Location:Cleveland, Ohio
  • Local time:09:10 PM

Posted 31 May 2008 - 05:29 PM

I'd lean towards a bad power supply. If you can get it to turn on with this method, you might have another problem:

The purpose of this procedure is to bypass the motherboard to test the PSU.

This procedure will involve working with live 12VDC electrical potentials which if handled improperly may lead to electrical shock. Proper precautions should also be taken to prevent electrostatic discharges (ESDs) within the case of the computer. For safety purposes please follow the instructions step by step.

First, shutdown your computer. Then unplug the power cable going into your computer.

Once you have opened the case, touch the metal of the case to discharge any static electricity.

The connector of the PSU which connects to the motherboard is readily recognizable by the number of wires in the bundle. To disconnect it you will need to press on the plastic clip to disengage it and then pull the connector up and away from the motherboard. Please take notice of the location of the locking tab and the notch on the socket of the motherboard, this will only connect one way as it is keyed. This wire bundle will have a memory of the way it has been installed and will want to bend back that direction, you may have to play around with it to find a position that the connector will stay in the same position while you run the test.

Posted Image

From the top left to right the pins are 13-24, the bottom from left to right are 1-12.

Please notice that there are PSUs with 24 pin and 20 pin connectors, the location of the green wire in the 24 pin connector is #16, and the green wire in the 20 pin connector is #14. If you look at the connector with socket side facing you and the clip on the top the number one pin will be on the bottom left corner. This makes the pin out for the 24 pin connector from left to right 13-24 on top, and 1-12 on the bottom. The pin out for the 20 pin connector from left to right is 11-20 on top , and 1-10 on the bottom. If you look at the connectors you notice that these are sockets that fit over the pins on the motherboard where the PSU cable attaches, this is where you will place the jumper. For a jumper you will need a piece of solid wire about the size of a paper clip (20-22 awg), preferably a wire with insulation. It will need to be large enough to fit firmly into the socket so that it will not need to be held in place while testing. You are at risk of electrical shock if you are holding the jumper when you power up the PSU. Insert one end of the jumper into the socket of the Green wire, and insert the other end into the socket of any Black wire.

Once the jumper is in place plug the cord back in. If the PSU is working properly the case fans, optical drives, hdds, and LEDs should power up and remain on. I would suggest that you not leave this connected any longer than is necessary for safety purposes.

To reconnect the 20/4 pin connector unplug the power cord, remove the jumper, and reconnect the connector. Take a moment at this time to make sure that nothing has been dislodged inside the case.
Posted Image
why won't my laptop work?

Having grandkids is God's way of giving you a 2nd chance because you were too busy working your butt off the 1st time around
Do not send me PMs with problems that should be posted in the forums. Keep it in the forums, so everyone benefits
Become a BleepingComputer fan: Facebook and Twitter

#5 Sneakycyber


    Network Engineer

  • BC Advisor
  • 6,135 posts
  • Gender:Male
  • Location:Ohio
  • Local time:08:10 PM

Posted 01 June 2008 - 01:06 PM

Check and make sure your CPU fan is turning on properly, The cpu will shut down and stop processing information (screen freezes) and it won't turn back on until it reaches its thermal rating which is possible why your computer won't turn on immediately after powering it down. I had this problem on an old slot A AMD processor and it turned out to be the fan. The power supply could also be suspect if its overheating.
Chad Mockensturm 
Network Engineer
Certified CompTia Network +, A +

#6 Bowserjoe


  • Members
  • 8 posts
  • Local time:09:10 PM

Posted 05 June 2008 - 11:15 PM

This is definitely a PSU problem. I had a similar problem a while ago. The 450 watt PSU that came with my comp lasted for about 3 years and then suddenly would not turn on anymore. The fans and LED lights came on for about half a second and that was it. After pushing the power button well over 200 times (literally), the computer would finally boot, but then it was only a matter of hours before it would shut itself down again. I installed a new 700 watt PSU and the comp worked like new again instantly!

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users