• Happy holidays, folks! Thanks to each and every one of you for being part of the Tom's Hardware community!

{possible} bad power jumper connection--Help please!

alsmith75

Reputable
Nov 24, 2014
4
0
4,510
I have an ASUS P6T MOBO, that has a known short somewhere that I've lived with for some time--it would power on by only the PSU switch in the back. It's been fine like this for over a year, with an i7 920 OC'd to 3.8, 16 GB of RAM, and a ASUS 670 DirectIICU video card

I want to sell this machine, and have taken it apart, and thoroughly cleaned everything, and tried breadboarding it to determine if the short could be fixed.

It seems the power jumper is bad--even shorting it with a screwdriver doesn't work, and now the only way to turn the computer on is the MOBO switch.

Does anyone know of a work-around --other than drilling a hole in the side of the case for a pencil or straw to create a new "power swtich" where I'd be able to press the MOBO power button--- where something could be soldered and or pins shorted to where I could have a functioning real power switch?

I've scoured the Net, and can't find any instances of a bad power jumper on the panel.

Running with a new Corsair 750W PSU

Thank You
 
Solution
Well, then that rules out my theory that the PSU was the culprit. Looks like you have a defective MB after all. There's not anything I can think of to fix it. The switching circuit is all done via transistors on the board. May be best to sell it with that disclaimer.
No, the power button on case does not work, and has been troubleshooted already by switching the reset switch, and switching polarity of the wires [installing case wires backwards]

the 2 pins for the power on the panel block do not power the MOBO --even when shorting it with a paperclip or screwdriver.

I do not have an Ohm meter, but even if it were to test as a fail, I am at a loss of what to do
 
Then likely the problem is in the PSU or the 24 pin cable. The MB may be sending the signal to the PS_ON# but the PSU's circuit isn't receiving it.
Do a little test. Unplug the PSU's wiring from the system. Do the paper clip test on the 24 pin cable and see if the PSU turns on when the green and the adjacent black wire on the connector is shorted. Have the PSU plugged in and its switch turned on when you short the terminals.
 
Well, then that rules out my theory that the PSU was the culprit. Looks like you have a defective MB after all. There's not anything I can think of to fix it. The switching circuit is all done via transistors on the board. May be best to sell it with that disclaimer.
 
Solution
Thanks much for your help--- it works perfectly fine--save it has to be turned on with the MOBO power switch. I was hoping for some sort of work around, but I guess not. I'll make up a new "power switch" with a pencil, and some paint with a hole in the side of the case.

perhaps I could label it as a security measure--unknowing people won't know how to turn it on 😛

The thought of bringing it in to fix it--[if it even can be] --I would spend as much getting it fixed as I would profit from the sale.