Coil whine in S12-II 380 Bronze

line · Post by **line** » Tue Nov 17, 2009 10:48 pm

Hi guys,

This is the sixth Seasonic "bronze" power supply I have recently bought, and the first to give me trouble.

So far I got:

2 x 430 Bronze
2 x SS-350ET
2 x 380 Bronze (I should mention that the 380s came from another supplier, who is not the official distributor, because the official distributor was out of stock at the time.)

Unfortunately, this one makes a loud whine noise when the system is powered off and current is drawn from the 5V standby rail. The noise varies in frequency and loudness depending on load.

I could stop the noise by cutting off the 5VSB wire (through the use of a modded ATX extender cable) but then the motherboard would not turn on.

I tried the power supply with a different motherboard from a different make to confirm that the noise does not come from the motherboard and is otherwise not triggered on the power supply's side by the specific motherboard design.

This comes as a great disappointment to me, because Seasonic has been my favorite brand, and the lower end S12s are incredible value where I live. Coil whine is perhaps the worst issue of them all, because it doesn't count as a defect.

I don't have any of the above units anymore, but I'm sure that at least the 430s didn't whine. I had installed them in very quiet systems, so I would have noticed.

Anyway, I would be thankful if you guys could help me reassess the "risk" of continuing to work with the S12s. Has anyone else bought a bunch of S12-II Bronze models recently? Did you also run into a coil whine issue? What is the chance of this being a fault specific to the 380 model, seeing as it's probably practically the same design as the others? And what is the chance of this being the result of rough handling in transit?

loimlo · Post by **loimlo** » Thu Nov 19, 2009 6:26 am

I suggest returning the defective 380W and grab a new one. Generally speaking, I've met coil whines across the vendors which led me to believe it's specific to one sample. For example, Gigabyte 2600XT did disturb me with coil whine, but Gigabyte 9600GT served me well enough. That said, Enermax PSUs tend to torture me in the past as I've successively encountered 5 defective PSUs generating coil whiiiiine.

line · Post by **line** » Thu Nov 19, 2009 8:32 pm

I don't think I can do that. Coil whine does not count as a defect outside our circles, and if I wanted to exchange a 'working' unit I would have to go through more trouble than I'm willing to take in this case. I need a solution that works with the system.

Thanks for sharing your experience. Yeah, it would appear that coil whine can basically hit you randomly. I guess I can only hope it won't hit me again.

Kaleid · Post by **Kaleid** » Fri Nov 20, 2009 3:45 pm

I had a Seasonic 500w PSU a few years back which had some buzzing problems. It was almost 100% solved by a Silverstone PSU-cover:
http://www.silverstonetek.com/products/ ... pp02&area=

line · Post by **line** » Sat Nov 21, 2009 4:14 pm

Nice device.

line · Post by **line** » Sun Dec 20, 2009 10:13 am

Got 4 x S12-II 330, not a problem with any of them.

Wayne Redpath · Post by **Wayne Redpath** » Sun Dec 20, 2009 3:31 pm

Sometimes electronics equipment make strange noises before they "smoke". Perhaps yours will make smoke very soon and then you can get a replacement.

line · Post by **line** » Tue Apr 13, 2010 2:23 pm

I seem to buy many of these so I figured I should post an update.

I have since purchased another 8 of the S12-II 330 Bronze and have not had a whining issue with any of them. One of them had a QC issue where the fan blades hit the grille which resulted in ticking noise. I sent it back but the shop technician was unable to hear it (they're really good for nothing as far as noise is concerned) so I ended up repairing it myself.

I'm ordering another 5 today, gotta wonder how long before they're gone too.

So far, none of the units I have bought over the years failed on me. Congrats Seasonic!

Alexander01 · Post by **Alexander01** » Tue Apr 13, 2010 3:02 pm

How silent is the S12II 330 Bronze? Can you hear it with a system with one fan running at 400rpm (and no harddrive noise). I'm planning to get one of these in an almost passively cooled system.

When will SPCR test this S12II 330 Bronze?

line · Post by **line** » Tue Apr 13, 2010 4:13 pm

I don't have my silent rig anymore and, frankly, it has been a while since I last attempted real silencing, but I'll try to answer your question. No, this unit is not silent. If you're careful with hardware selection, it'll quickly become the loudest component. I could hear it over an 800rpm Arctic Cooling 7 Pro and 600rpm S-Flex fans. The noise is both airflow and low-frequency hum. You'll hear it over the 400rpm fan, so be prepared to do something about that.

You should be able to swap out the stock Adda fan for a Scythe S-Flex 1600rpm model and make it near-silent. The S-Flex would spin at under 500rpm. I haven't done that myself, but it should be an easy swap. You can also get soft fan mounts like these or these and try them with the stock fan or the S-Flex.

For what it's worth I can add that the startup noise of the S12-II 330/380/430 models is the same, so there's really no point in spending more money if you don't need the watts or extra connectors (the 330 ships with one 4-pin cpu connector, and one 6-pin PCI-E VGA connector). It is possible that the higher-wattage units can take up more heat before the fan ramps up, but even with the 330 that won't happen too soon. Of course, using a case with bottom power supply mounts helps a lot. The fan controller in this psu design is strictly guided by temperature, not actual load.

Comparing it to other units (from memory) The S12-IIs are a bit quieter than the OEM Seasonic SS-350ET and equal to or a little quieter than the Corsair VX450W. They're definitely louder than the Enermax Pro82/Modu82 425/625 I had at the time but I hear those models had their own share of problems.

line · Post by **line** » Tue Apr 13, 2010 4:24 pm

Since you asked about silencing I would like to add that on several occasions, after installing the S12-IIs in relatively quiet systems, I noticed buzzing noise (mid-frequency) that coincided with HDD access. It wasn't too loud to be bothersome but could be an issue if you aim for silence.

I could never figure out where exactly it came from -- the motherboard, or the power supply. That said, many of the systems I deal with are old so it is possible that new systems are not affected. I also don't know if SSDs are affected. Still, I thought that is worth mentioning in case someone can expand further.

Alexander01 · Post by **Alexander01** » Wed Apr 14, 2010 5:08 am

Thanks for the reply. Very useful info.

I will only use 1 SSD in the system and no harddrives.

I saw a few topics about replacing ADDA AD1212MB-A71GL for a S-Flex 1600.

My only question is: What type ADDA fan does the S12II 330 Bronze have?

I saw the new Seasonic S12II 520 has a ADDA AD1212MB-A70GL Fan (test @ jonnyguru.com)

Is it different from the 71GL?

Can you tell me if the S12II 330 Bronze has the A71GL?

Thanks very much!

line · Post by **line** » Wed Apr 14, 2010 3:40 pm

I found a page that explains the fan numbering scheme:

http://www.adda.com.tw/eng/fans_model.php

The relevant sheet is probably DC Fan -> OLD. It seems the 0 & 1 describe the motor internals, 0 for "impedance" and 1 for "IC". I don't know what that means but sure, I'll open up one of the new ones and let you know the fan model.

Alexander01 · Post by **Alexander01** » Sun Apr 18, 2010 5:46 pm

Seems there isn't much difference between the A71GL, A72GL, A73GL.
Current/Power/Speed/Air Flow/Pressure/Noise are the same on all these A7*GL models according to this pdf: http://www.addausa.com/specifications/92-120.pdf

I think it's the same for the A70GL.

line · Post by **line** » Mon Apr 19, 2010 8:50 am

Ok the fan is AD1212MB-A71GL. I did not need to open up the psu, it was visible through the exhaust grille.

ralphzak · Post by **ralphzak** » Thu Apr 22, 2010 7:48 am

I saw a motherboard where it was possible to turn it off at the keyboard port and the USB port. causing it to use 5V instead of 5VSB.
I guess one couldn't turn off 5VSB completely though..

I'm pretty sure I have 2 solutions funnily enough..

Another idea.. Is another power supply giving 5V .. A cheap way is to use a power brick adaptor that comes with a USB-IDE adaptor. Those power brick adaptors, have a mains plug on one end, and a 4-pin molex on the other end. The red wire from the molex connector would carry 5V and could do so continuously. You could cut that and extend it, then it's a question of just attaching it.
On your expensive power supply that is plugged into the motherboard, the atx connector's purple wire would be 5VSB if memory serves right (50/50!). You could simply cut that wire and connect the red wire.

Here's another solution.. I think I found this during experimentation a long while back. Thinking of solutions for a KVM that didn't like 5VSB coming out keyb and usb.

The 5VSB wire is only needed when turning the computer on.
You can cut the 5VSB wire.
(then, when you want to turn the computer ,on you join it and push the on switch, or connect the ON pins)
Then it's on, and you can stop holding the 5VSB together.

You could even put the 5VSB wires on a switch. So once the computer is on, you could switch off the 5VSB circuit.

line · Post by **line** » Thu Apr 22, 2010 2:43 pm

Hi Ralph & welcome to SPCR.

I appreciate your suggestions.

If I had to come up with a solution (right now it's okay -- I have not received any complaint), I'd probably go with your last idea to cut off 5VSB once the computer is on. Rather than mod the case to install a new switch, I could probably reroute the 5VSB wire through the reset button.