BleepingComputer.com: COMPUTER WON'T TURN ON

MY HP 716N HAS THE GREEN LIGHT IN THE BACK OF THE COMPUTER ON ON ,BUT WILL NOT POWER UP. THE POWER BUTTON HAS NO LIGHT OR NOTHING HAPPENS WHEN I PRESS IT. CAN I GET SOME ADVICE ON WHAT COULD BE. THANKS FOR ANY HELP.

Make sure its properly plugged in ( In case you didn't already check that). After that I would start with the power supply. The purpose of this procedure is to bypass the motherboard to test a ATX PSU. Some manufacturers Like Dell have used some non ATX PSUs which have a different pinout for the 20/4 pin connector, please confirm that your PSU is a ATX type before using this procedure.

Caution: 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.



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.

thank you for a fast reply, i have another hp computer similar ,this one its a 750n pavilion and i switch the power supply to the 716n and when i press the on button it turns on for about 5 seconds and goes off again. should i replace the power supply or should i try first what you told me to do with that test. thank you

I would replace the power supply. Buy a good one too. The cheap ones do not last.

So you took the good power supply and put it in the bad computer? or you took the bad power supply and put it in the good computer. If the power supply made the good computer crap out then its bad replace it with a similarly rated power supply (same wattage [unless you plan on upgrading]).

no , i took the good power supply from my 750hp and install it on the 716n and the power comes back for about 5 seconds and then goes out again, i have not try putting the power supply on my running computer, cause i'm afraid if its bad it may damage my good computer.

I would be suspect of a bad component. Remove all of your expansion cards leaving only the Video card (if its not integrated into the motherboard) Un plug any unnecessary Hard drives and cd/DVD rom drives. Leaving only the Motherboard, CPU, and Video card plugged into the motherboard. Power up the computer. When the computer powers up pay close attention to the CPU fan, the Video card Fan (if so equipped) and the Case fans make sure they are working properly. If the fans work and the computer still shuts down it could be a CPU or motherboard. Lastly before replacing your power supply I would test it to make sure its bad. If the computer did NOTHING before and now it turns on for a few seconds I think the old one is dead. If the old one is dead it may have taken the motherboard out with it.

Could be an overheating issue. I'd check to make sure that the CPU fan is working right.

I uhh umm dah never mind

Sneakycyber, on Oct 1 2009, 06:45 PM, said:

LOL, I said the same thing when I read the post right before yours. You have been very helpful on this thread. Good detailed information.

Adding to a dead thread:

I ran across this in a customers HP of the same vintage last week, and it would still boot into XP half the time:




8 trashed caps, and it still tried to boot.