GA-X58A-UD3R or PS problem?

[Dramey]

This is the wierdest computer problem I have ever seen. I picked up a new Corsair power supply to go with the GA-X58A-UD3R. Once I got it installed I noticed a strange squeaking noise coming from the computer when it was off. It was the PS fan pulsating like it was geting a jolt of power every couple seconds. It continues to happen even with the plug pulled from the PS. I also have some lights on the MB that stay on. Ok, I'm thinking there must be some sort of capacitor problem with the PS. I remove the PS completely and the fan stops, but the MB lights stay on. With the PS sitting in my lap, if I connect the main power to the board the fan starts up again. I left the machine unplugged all last night and it was still doing it this morning.

I didn't notice the old PS doing this, but I only had this board hooked up to it a couple days, and it's fan may have just been quieter.

Ay ideas where my problem lies? Board or fan?

[Dark Mantis]

Hi and welcome to the Gigabyte Forum.

Well you definitely have a problem there but which part is causing it is hard to say at the moment.

Try removing the PSU from the mains and then unplugging the 24 pin power cables and 12V power cables off the motherboard and then plug the PSU back into the mains. Does it exhibit the same symptoms?

If it does then the PSU itself is faulty.

The PSU is supposed to supply a residual current to the motherboard for charging the USB connected devices even when the computer is powered down, but it shouldn't pulsate like that.

[Dramey]

I swapped out the PS yesterday for an identical model and it is doing the exact same thing. I can hear the fan pulsing in the other room right now, and it's been unplugged since last night.  I guess I need to RMA the board, but I'm afraid to handle the thing if the caps are holding and leaking that much power

[Dark Mantis]

I can hear the fan pulsing in the other room right now, and it's been unplugged since last night.

If the power supply has been unplugged from the mains all night where is it getting it's power from the pulse the fans. Even the biggest PSUs with very large capacitors would self discharge in a matter of minutes!

[Dramey]

That is my question exactly. Literally the only power in the case is the CMOS battery. I think my computer needs an exorcism.

[Dark Mantis]

What USB devices do you have plugged in at the time as I'm wondering if it could be drawing some power from them.

[Dramey]

None. Unplugged everything, even the drives.

[Dark Mantis]

Well the power is coming from somewhere.
If everything is unplugged try pushing the start button and see if that drains all the residual power and the fan stops.

[Dramey]

For the record I did finally figure out where the power was coming from. Via the displayport on my 6970. As soon as I unplugged that monitor, the problem disappeared. I guess the displayport input on the monitor is leaking power back in to the computer. I put my old video card in and still had the problem. I switched that monitor to hdmi and all is well.