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Mcpisik
02-01-2010, 04:22 PM
Hi folks...
My old pc (one is my sig) is not turning on.
Has light on mobo.
No fans running etc.
Studied on net how to multimeter test psu and all seems good to my knowledge...

So as the power switch does nothing, I've shoved a paper clip into the 20pin mobo connector, in a black and green position.
This has booted the pc.

Is this just a non functioning power switch?
I tried to short the power connection on the mobo, but didn't work hence why I ask...oh and also, should I leave the paper clip in there and use the psu switch for on/off (until I fix it)

Cheers!

pctek
02-01-2010, 05:33 PM
I've shoved a paper clip into the 20pin mobo connector, in a black and green position.
This has booted the pc.




How did it? If you haven't got the connector in the board, it can't boot.

Mcpisik
02-01-2010, 05:55 PM
How did it? If you haven't got the connector in the board, it can't boot.
Sorry, I meant powered up...
Fans, optical drives etc power up.

The 20pin connector is not attached to the mobo while paper clip enables power.

Could you suggest what might be at fault with the system?

Would be appreciated thx...

Speedy Gonzales
02-01-2010, 05:56 PM
If it boots by shorting it, the front of the case is stuffed. Replace the case. So does it have a 20 pin connector, or not?

Mcpisik
02-01-2010, 06:09 PM
Cheers Speedy,
Yes has a 20pin connector..

So if I replaced the power switch only, that should do it?
(It's a thermaltake armor case, so would rather not throw it away)

I couldn't get it to boot by shorting on the mobo (2 pins where the power switch connects to) Perhaps I'm not doing it correctly or shouldn't be...

(But I wouldn't know the difference between shorting the 20pin or the mobo)

wainuitech
02-01-2010, 07:34 PM
I couldn't get it to boot by shorting on the mobo (2 pins where the power switch connects to) Perhaps I'm not doing it correctly or shouldn't be... Did you remove all the plugs from the connector / header ?

You need to have them all removed other wise one still may be the cause, then take a flat bladed screwdriver and touch the two pins that are the power As shown Here (http://www.imagef1.net.nz/files/Power.jpg) you have to make sure there is contact, this should kick the board into life, then pull away the screwdriver. All the switch is doing is the same thing, making contact.

The wire "trick" is just that, normally a mother board has to have the Power Connector in its socket and the PSU gets a signal from the board completing the circuit, the wire in the plug tricks the PSU into thinking its connected, and fires up the fans etc.

Mcpisik
02-01-2010, 07:57 PM
Did you remove all the plugs from the connector / header ?...
Thanks...
From the image you gave, I was touching the correct pins.

Excuse the ignorance, but what is the header/connecter that I remove the plugs from?

bob_doe_nz
02-01-2010, 08:10 PM
The white plastic receptor/portion on the motherboard that accepts the 20 pin power supply connector.

wainuitech
02-01-2010, 08:14 PM
The Header is the front panel connector, this supplies the connection point for the HDD LED, power LED, Power Connection,Reset and in this case the Speaker.Front Panel Header (http://www.imagef1.net.nz/files/FP.jpg)

You need to remove all the wires going to this header,not just the power, if one is causing the problem in the switch it can stop the rest from working correctly.

You can also try changing the CMOS battery - that may have died, they are about $3.

IF the boards still not booting - it is possible its died.

BOB- I was referring to the front header, not the Power Socket :)


I've shoved a paper clip into the 20pin mobo connector, in a black and green position.
This has booted the pc.
Do you mean it booted the fans only ???

Paul.Cov
02-01-2010, 08:45 PM
I had an issue like this not too long ago... but in my case the power button was stuck in the pressed in position, and it needed a bit of gentle prodding to get it to move freely again. Checked the reset button at the same time, and it was also getting sticky.

Hey, as for those wires to your power button - trace them back to where they plug into the motherboard, and give each one a bit of up-down movement to scrub their contacts against the pins.

bob_doe_nz
02-01-2010, 08:51 PM
BOB- I was referring to the front header, not the Power Socket :)

Oops :blush:

Agent_24
02-01-2010, 11:01 PM
Sounds like a problem with the power switch or the power switch circuitry.

Check the BIOS battery also. Very strange things can happen if it's flat.

Though I wouldn't rule the PSU itself out either. Do you have another you can try?

Mcpisik
03-01-2010, 07:40 AM
Thanks to the last few replies...
I'll replace battery tonight.
Took off all cables from the header and tried to short it, but no luck there.
Twould be so nice if it's a flat battery!

Mcpisik
06-01-2010, 02:10 PM
Doh, battery replaced but still no go...
Any suggestions where to go from here?

Would replacing the mobo be next step?
Are there any tests I can do that would tell me if that's fried?

Or is it best to take it in to a shop at this stage...
Thanks...

Agent_24
06-01-2010, 02:38 PM
When you manually jumper the PSU and force it on, does the system run normally?

Wait, I see from your previous posts that the 20-pin connector was not plugged in when you did this.

It could be a problem PSU. Have you tried another? I once had one that was faulty and would power up by itself.

Mcpisik
06-01-2010, 04:59 PM
It could be a problem PSU. Have you tried another? I once had one that was faulty and would power up by itself.
I'll try getting hold of another....hmmm might even grab an old one off trademe. Would certainly be best if it is the psu...
Cheers

Mcpisik
11-01-2010, 09:10 PM
So, new psu installed and has fixed initial problem.
Now boots to bios...

However my hard drives are not being recognized.

(I did replace the cmos battery and have readjusted the time/date, but will the battery replacement affect much else?)

It could be something super simple, but if anyone knows what could stop the hd's being recognized, please yell out :)

Agent_24
11-01-2010, 11:41 PM
Battery replacement would have reset all BIOS settings to defaults - There might well be a setting that was altered that is causing the drives to not be detected.

What drives do you have and how are they connected, and which motherboard do you have?

Do you know if the drives spin up?

Mcpisik
12-01-2010, 06:48 AM
Hi,
Didn't sound like the drives were spinning up.
It's the pc from my signature...
They have sata connections.
Thanks for the reply...

Agent_24
12-01-2010, 10:22 AM
Confirm that the drives spin, remove data cables, leave only power and try again.

Mcpisik
18-02-2010, 01:45 PM
...just an update to this problem...
New hd blew when plugged in (and a few others as well blew instantly when connected)
New psu(s) didn't change anything.
So still no idea what is causing hard drives to blow. Gulp
And don't know if I can salvage the graphics card or sound card, memory etc...
Am ready to throw the whole thing away now as 2 different repair shops dont know the cause...and I sure don't have any further ideas...
Yell out if anyone needs a brand new psu! (or 2)

Agent_24
18-02-2010, 02:19 PM
Which PSU did you get and where did you get it from?

You didn't plug the HDD in while the PC was turned on, did you?

pctek
18-02-2010, 03:19 PM
...just an update to this problem...
New hd blew when plugged in (and a few others as well blew instantly when connected)
New psu(s) didn't change anything.

Am ready to throw the whole thing away now as 2 different repair shops dont know the cause.

Then that leaves the board itself if you've swapped the PSU.

Mcpisik
19-02-2010, 06:04 AM
Which PSU did you get and where did you get it from?

You didn't plug the HDD in while the PC was turned on, did you?
Nope, safe install...
PSU was Western Digital Caviar Green WD10EARS, 1000GB, 5400-7200rpm, 64MB Cache, SATA-2

gary67
19-02-2010, 06:33 AM
No that's the HDD what is the PSU?

Mcpisik
19-02-2010, 06:40 AM
No that's the HDD what is the PSU?
Ha! copy and paste doesn't work so well early in the morning! (at least my eyes don't...)
Vantec ION2 Plus, 600W ATX PSU, Active PFC, SLI Ready

Agent_24
19-02-2010, 11:49 AM
You say the HDD blew, do you know which part of it exactly? Can you post a photo?

Mcpisik
19-02-2010, 11:53 AM
You say the HDD blew, do you know which part of it exactly? Can you post a photo?
Probably more like, won't spin up after pluggin in.
We tested one with another pc prior, then again after using in this pc, which wouldn't fire up again afterwards...