Seasonic S12-380W high pitched whine with Asus P5B-VM

specular · Post by **specular** » Wed Oct 04, 2006 11:34 am

So I've put together a new system consisting of:

Asus P5B-VM
Core 2 Duo E6300
Antec Solo
Seasonic S12-380W
IDE HD
DVD-RW

Everything's fine except for the Seasonic. When the machine's in Windows, it emits a fairly loud high pitched whine, which could be coil whine. I've localized it to the Seasonic by taking the PSU out of the case, and it's definitely coming from the PSU.

The strange thing is that when I'm in the BIOS editing screens or running a DOS based diagnostic, there's no whine at all. It happens only when I'm in Windows, even if I'm just idling.

I first suspected that the whine is related to the CPU's power saving modes. When I watch Asus's Probe, it shows ~1.12 V for the CPU's voltage after boot. But if I mess with Asus's AI Gear or AI Nap (which adjust power usage) so that it somehow raises to voltage to 1.25 V, the whine stops for the most part (though it sometimes comes back for a sec or two at a time, which seems to be related to when I'm clicking around in Explorer).

Then I suspected that the whine is happening when there's not enough total current being drawn by the system, with the CPU in a low power mode dropping the total current below a certain threshold. So I hooked up a second DVD drive, and the whine disappeared again, even without my fiddling with the CPU power settings (except for those intermittent bursts again).

Has anyone else experienced something like this? Is this a sign that my PSU defective or borderline and should I send it to Seasonic for another? Any thoughts or advice is much appreciated.

Engineer · Post by **Engineer** » Fri Oct 13, 2006 4:59 pm

I just bought the 550W S12 Energy plus model and it made a whine/buzzing sound. I had read that if the power is too low on certain rails of the supply, it would whine/buzz. I turned power management off ("Minimal Power Management") and the buzz/while instantly disappeared. I had the same whine in the Antec NeoPower 480 but it didn't go away with power management turned off.

Now all I can hear is the Seagate 7200.10 drive which i might have to do something about as it's now obnoxious whereas before, I noticed the buzz/whine before that.

You might not have enough load on the PS to avoid the whine/buzzing sound. Makes me wonder if one could add a small resistor across the rails (either 5 volt or 12 volt) and get rid of it. hmmmm

jaganath · Post by **jaganath** » Sat Oct 14, 2006 12:54 am

It's ironic that with the Energy+ you actually have to make your rig less efficient to reduce noise; normally it's the other way round.

Engineer · Post by **Engineer** » Sat Oct 14, 2006 6:53 am

jaganath wrote:It's ironic that with the Energy+ you actually have to make your rig less efficient to reduce noise; normally it's the other way round.

So true. However, I will say this. The air exiting out of the rear of this power supply is barely warm compared to nearly "HOT" air coming from an Antec NeoPower 480 that it replaced. I think I'm still coming out ahead in the long run!

Engineer · Post by **Engineer** » Sat Oct 14, 2006 12:08 pm

Update: After the PC sat overnight and the house cooled, the noise returned, but at a lower level. Any PC benchmark (loading up the CPU) cured the problem. I finally tired of hearing the noise so I went to Radio Shack and purchased two 10-Ohm wirewound 10 watt resistors. I soldered them series and then to a Molex connector on the 12v side. I attached them to the side of the drive rack in front of the intake fan and hooked it up. Buzzing sound is completely eliminated.

It is sad that I have to load up the power supply to stop the buzzing. Maybe later I'll throw in a Kentsfield quad core and eliminate it the natural way!

Edit: Well, while the 20 Ohm resistor combination worked, it became very hot and actually raised the temperatures in my case by as much as 8C (various components). I hooked another 10 Ohm resistor in series and tried the new 30 Ohm combination outside the case attached to the fan grill. No noise and much cooler now. Just make sure not to touch and of the leads to the case if trying.

boba8888 · Post by **boba8888** » Mon Oct 23, 2006 5:20 pm

Hello.. I just built my first box .. nothing fancy :
ASUS A8N5X mb
AMD 3500
PNY GeForce 6600 vid
Seagate 7200.1 320GB
1GB stick memory
Sony DVD/CD
Seasonic 380W psu
I have the exact same issue. I have put my ear right up to the PSU and it is definetly coming from that source. Have never fiddled w/PSU's but I dont believe it's the fan, I have heard funky fans before.. this sounds like a electrical buzz. Don't hear the noise while in BIOS and it goes away while loading a video demo. Noise starts exactly when XP Home startup screen appears. It seems to go away for a few seconds when loading up a application, etc.. basically the PSU goes quiet under load.. only for a few seconds.
So I called Seasonic support and after reviewing my setup he tells me to buy another 1GB stick.. and I am like WHAT ? He proceeds to inform me I have to run 2 sticks cause dual channel mb.. blah blah and then the noise will go away. Of course this didnt work.
Regardless I have RMA'd the PSU in hopes that a new one will fix it.. if not, do a return and move onto another PSU. Just wondering if anybody finally addressed this issue. I would really like to keep this PSU due to great reviews and nice design.. thanks !! Bob

specular · Post by **specular** » Mon Oct 23, 2006 10:00 pm

boba8888, when you get the replacement PSU from Seasonic, could you report back to this thread to let us know if the replacement solves the problem? Most of my whine is gone since I've added a load, but it's still somewhat annoying when the intermittent bursts happen.

Thanks for everyone's input so far.

boba8888 · Post by **boba8888** » Tue Oct 24, 2006 9:22 am

Spec,
I certainly will. My hunch is that the buzz/whine won't go away. I even thought, as you did, to add more hardware/software to increase load. I only have a external USB drive, USB mouse to add. I also was only running a clean XP install with no other software. I plan to try to thoroughly test it out when I get the replacement. I am guessing like a week from today.. and I agree, that noise is beyond annoying !! later

boba8888 · Post by **boba8888** » Tue Oct 31, 2006 3:25 pm

I received the new PSU and the electrical buzzing has stopped. So my gut now tells me the first PSU had issues and all is well now.

specular · Post by **specular** » Tue Oct 31, 2006 9:44 pm

That's good news, boba8888. So did you do an advance exchange with Seasonic? Did you have any problems with the process, and any tips you learned along the way? I'll probably do the same thing.

Thanks for coming back to let us know what happened.

vg30et · Post by **vg30et** » Tue Nov 21, 2006 8:12 pm

Rather than start a new thread, I thought I'd post in here. I too have a S12-380W that has been making an annoying high pitched intermittent buzz/whine on a different mobo but only when there is no load. Noise goes away when CPU burn is run.

I have swapped the power supply into 2 different systems, Sempron 2700+ & AM2 X3800+ and the S12-380 produces the annoying noise in both. To rule out other components, I swapped in my Corsair 620W and the buzzing disappears.

I went ahead with Seasonic's RMA process and was sent another S12-380 but this one whines just as loud, if not louder than the old one. Same thing in both systems - Seasonic = loud buzz, Corsair = silent.

I have emailed Seasonic for their recommendations but will welcome any suggestions anyone may have...

UK-Bob · Post by **UK-Bob** » Wed Nov 22, 2006 4:48 am

Very interesting as I have been looking at the S12 380w for my own system. Could this whine be cured by adding a cap to help smooth the signal rather than a risistor to load it ? I also have the smae problem with a light bulb running from a dimmer. When the dimmer is turned down the bulb produces this same whine and is very distracting !

jaganath · Post by **jaganath** » Wed Nov 22, 2006 5:59 am

It's weird because the Corsair is also made by seasonic, so whatever is the difference between the S12-380 PCB and Corsair is the problem.

specular · Post by **specular** » Wed Jan 10, 2007 11:01 pm

Seasonic replaced my original S12-380W PSU and thankfully the replacement does not whine. If I listen really carefully, I can hear a slight ticking sound from the fan, but from a normal distance I can't hear it. So I'm satisfied now.

RaptorZX3 · Post by **RaptorZX3** » Mon Feb 05, 2007 10:02 pm

i just hope my S12-380W won't do that whine sound...

my power scheme is set at "Home/Office Desk"

JaYp146 · Post by **JaYp146** » Mon Feb 05, 2007 10:20 pm

Has anybody experienced this problem with a Seasonic S12-430 PSU? It seems like these are mostly 380 horror stories ...

RaptorZX3 · Post by **RaptorZX3** » Mon Feb 05, 2007 10:32 pm

i think some peoples had this problem with the 330W and the 430W. not sure if it's a rare defect or something...

sslamster · Post by **sslamster** » Thu Feb 22, 2007 12:38 pm

Hi all:

See this thread which may address some of your questions/concerns:

viewtopic.php?t=37023

There is an issue with some of the ANTEC SU380 & Seasonic 380 supplies.

RaptorZX3 · Post by **RaptorZX3** » Thu Feb 22, 2007 12:42 pm

well mine doesn't do that whine noise on my Asus A8V-E SE

sslamster · Post by **sslamster** » Thu Feb 22, 2007 12:53 pm

From my experience it is unlikely that the buzzing is related to the hardware that you use, rather it is a function of the power supply itself.

Seasonic S12-380W high pitched whine with Asus P5B-VM

Seasonic S12-380W high pitched whine with Asus P5B-VM

Seasonic S12 380W buzzing here too..

RMA 380W arrived