Can I safely disconnect auxiliary power from motherboard?

404zero

Junior Member
Sep 20, 2010
2
0
0
Can the auxiliary power connector be safely disconnected from my motherboard without causing any problems?

I have a Dell GX520 mini tower that has noisy coil whine in the power supply unit, but only when the computer is off.

I'm guessing that it's the auxiliary power that keeps feeding power into the power supply when everything is turned off?

If it can be safely disconnected, would I just unplug the 12v 4-pin connector to disable auxiliary power?

Thanks for your help!
 

Rifter

Lifer
Oct 9, 1999
11,522
751
126
i have no idea what you are trying to say, how would the mobo be feeding power TO the power supply. And no you cannot disconnect the 4 pin connector, it needs that to power the mobo, usualy feeds the CPU vrm's.
 

taltamir

Lifer
Mar 21, 2004
13,576
6
76
Can the auxiliary power connector be safely disconnected from my motherboard without causing any problems?

I have a Dell GX520 mini tower that has noisy coil whine in the power supply unit, but only when the computer is off.

I'm guessing that it's the auxiliary power that keeps feeding power into the power supply when everything is turned off?

If it can be safely disconnected, would I just unplug the 12v 4-pin connector to disable auxiliary power?

Thanks for your help!

there is no such thing as auxiliary power connector on the motherboard... the 12v 4-pin connector is the CPU power line... and no, you cannot disconnect it.
If your PSU is acting up, replace it now before it fries your computer. its less than 50$... much cheaper than a new computer.

The PSU keeps on feeding power when the computer is "off", via the 20 (or 24) port cable, not via the 4 pin cable. the mobo uses that power to listen for wake up (aka, power up) commands (via keyboard wakeup button, power button on case, ethernet port wakeup commands, or alarm based wakeups where you set in the bios for the computer to automatically turn on at a certain date and time).
 
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lopri

Elite Member
Jul 27, 2002
13,314
690
126
I thought the OP was talking about molex or SATA power plug some of the boards (geared toward SLI/CF crowd)? Not the 4-pin/8-pin CPU power connector.
 

AstroGuardian

Senior member
May 8, 2006
842
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I thought the OP was talking about molex or SATA power plug some of the boards (geared toward SLI/CF crowd)? Not the 4-pin/8-pin CPU power connector.

That's what i thought too. If there is a molex connector somewhere aside from the 24 pin and 4 pin for the CPU and ou are not using sli/cf you can safely disconnect it. BUt i doub't that\s what is causing the noise. Might be a dieing motherboard...
 

404zero

Junior Member
Sep 20, 2010
2
0
0
So I guess my only option is to replace the power supply.

The question is, can I safely replace this BTX power supply with an ATX?

I've heard mixed opinions as to whether or not this can be done.

Thanks again!
 

Rifter

Lifer
Oct 9, 1999
11,522
751
126
I believe you will need to re-pin it, i had to do this on my dads dell when his PSU went. Just get the pinout for the dell PSU and the re-pin a ATX PSU to match it.