Desktop with Intel Dual-Core motherboard shuts down in two seconds

[jnjani]

Packard Bell Desktop with Intel Dual-Core motherboard shuts down in two seconds. CPU fan and PSU fan starts and shuts down immediately. Checked with spare PSU - No change Edited May 14, 2012 by jnjani

[KenB]

Hi and welcome to ExTS

 

This could be a number of things - but it does sound like hardware to me.

 

Switch off at the wall but leave the plug in.

This maintains the earth connection to the motherboard.

 

Try taking the RAM out.

Switch on with the RAM out of the system.

You should get POST beeps - if you do this is good :)

 

If you do get beeps then put just one RAM module back and try booting again.

If the problem returns - swap the RAM over.

 

Don't forget to switch off at the wall if you are going inside the case again.

 

Let me know the results in a little detail please.

[jnjani]

There is no POST beeps!

 

What next?

[KenB]

Right - no beeps indicates that there is possibly a problem with the motherboard or Power Supply Unit.

( this assumes that you were getting a single beep before ?? )

 

I have a tutorial that explains whet to do next - assuming that you have an internal speaker connected.

http://kenspchelp.co.uk/viewtopic.php?f=9&t=172

 

If you don't have an internal speaker still follow the tutorial - but you need to check that the system is stable and not shutting down.

If it is stable with all of the hardware and connections removed then putting them back one at a time and testing after each is the way to go.

 

The system should run the fans etc without restarting.

Adding the hardware etc one at a time ( testing after each addition ) will [ hopefully ] indicate the problem when the system crashes again.

[jnjani]

First of all THANKS for superb tutorial. If I could't fix this PC, this tutorial will always be informative and helpful. Now coming to issue, I assume that "internal speaker" refers to Buzzer on board (normally of black colour). If it is true, there is no single beep even. There is no extra hardware. What ever is there is on-board. System is not stable. There is no chance to check anything as it shuts down almost instantly. All I can see is PSU and CPU fan starts for two seconds only. I haven't made any change in hardware of software before this issue. I am sure there is no problem with power supply unit as same power supply works fine in other PC. Just to cross check I have tried other power supply unit with this PC and there is no change.

[KenB]

If you have removed all of the hardware and connections ( re Tutorial ) and you know the PSU is good - the only possible thing it can be is the motherboard.

 

You could try removing everything ( except the 20 way power connection ) unscrew the m/board and sit it on a piece of card or newspaper to insulate it from the case.

Switch on.

If it doesn't shut down then there was a short between the m/board and the case.

 

Internal Speaker ( 2 types )

[ATTACH=CONFIG]743.vB5-legacyid=1521[/ATTACH]

[ATTACH=CONFIG]744.vB5-legacyid=1522[/ATTACH]

[jnjani]

Well, this time there IS a change. Removed motherboard from case and started with only 20/24 pin socket. It doesn't shut down - But when I attached 12 volt it again shuts down as previously. There is no beep.

[KenB]

But when I attached 12 volt it again shuts down

Which 12v are you referring to ?

[jnjani]

Four pin socket with two yellow and two black wire

[timez]

Make sure the 4 pin connector isnt the +4 pin from the 20+4 pin connector - if you can clip it onto the 20 pin connector then its the wrong one.

 

There should be an extra 4 pin connector that doesnt clip onto the 20 pin one.

 

This assumes your PSU has a 20+4 pin connector - and not just a 20 pin one (as i say - test this by seeing if you can get the 4 pin one to go onto and stay on the 20 pin connector.

 

Timez

[jnjani]

Its a 12 volt square plug usually with two yellow and two black wire and entirely different from ATX 20 or 24 pin plug.

[KenB]

Hi

It seems that we have not kept this thread going - started in May :)

 

Is this the connection you are referring to ?

 

http://www.playtool.com/pages/psuconnectors/12v4pinindex.jpg

 

This is the 20 (4) connection - it has a red wire on the 4 pin connection

http://www.playtool.com/pages/psuconnectors/main20plus4index.jpg

 

Where on the motherboard are you connecting it ?

 

Will the system boot up if you leave it off ?

[jnjani]

YES, I'm referring to this connection (first photograph of white connector). I am connecting this connector at 'ATX 12 V' (located exactly opposite to 24 pin 'ATX POWER' connector) . System will not boot up if I leave it off.

[KenB]

System will not boot up if I leave it off.

 

If it is this one ( see pic below ) it is powering the Central Processor.

[ATTACH=CONFIG]927.vB5-legacyid=1810[/ATTACH]

 

In your first post you said that you had tried a spare PSU - no change.

 

It therefore looks like either the motherboard or CPU are at fault.

 

You could phone a local tech ( small one man business is usually best ) and ask if they can test them for you.

Also ask how much.