I have spent a long time searching through posts about PSU models and coilwhine in general. From what I can see a lot of people get it and on basically all brands/models of psu, and it is often to do with the gpu and psu combination. I tried different power sockets on different circuits in the house, and took my GPU out and used onboard video, which made no difference. So yes capacitors in the PSU circuitry look like the cause.
We have an upstairs ring and a downstairs ring in the house which I thought could of been causing a problem. I tried it at a friends house on his computer, and there was also the same hissing. There were mcbs there, but not sure about ring or radial power circuits.
Two Adults who were 60 couldn't hear any high pitched coilwhine at all, I'm 23 and can. Some other people who are 40 could only hear a faint hiss which bothered one, and not the other at all. Once its been noticed it is very hard to not listen out for (I listened for a month before replacing the first psu)
I Rma'd the first psu and quickly received another new EVGA Supernova G2 which also had coilwhine, only with a tiny bit more hissing. I could hear it from about 5 meters away from the case, instead of 1 to 2m close to it with the first psu. The second one hissed when no modular connections were plugged into it, so it didn't turn on and the only cable was the power in from the plug.
Sombody here (blog.szynalski.com/2012/11/24/in-search-of-a-quiet-psu) who had the same problem suggested that since the newer more energy efficient PSUs e.g. 80% gold, silver have been made and are popular, and that coilwhine has increased/is more likely to occur. (Over the last few years+). I think this too.
A forum user somewhere posted that he wrote to Corsair and received this response:
"The noise is not normal to the unit. It's very difficult to test units for audible noise in reality, because Corsair's test environment has a very clean power source. Many times, the noises come from the PFC filter circuitry or components used in the AC-DC conversion process, and these components all can react differently based on how clean the power source is. A unit that performs silently here in the lab may buzz or click in a house with older wiring, or using a failing battery-powered UPS, or any number of other things".
I would have thought that the wiring in my house is quite old, as we have cartridge fuses and no mcbs/rcds. But trying the psu in another house ruled my house wiring out I guess.
The Power factor supplying a house can't be made better, but some sort of correction for a single socket outlet may exist. A poor power factor will make capacitors work harder as the current is lagging the voltage. The psu might try to correct this to result in a purely resistive PF of 1. I don't know what the power factor in the house is.
Luckily I was able to refund the second EVGA psu. I looked around online for psus that don't hiss or are less likely to, there were a lot of people saying that corsair CX psus hiss. I noticed also that manufacturers, when listing psu specifications say a lot about the fans being designed to be silent. But nothing on capacitor noise (coilwhine), only that there are high quality capacitors.
I couldn't see many people posting about coilwhine with bequiet psus, and after seeing this review commenting on capacitor noise I went for a bequiet straight power 10 | 700w
www.guru3d.com/news-story/be-quiet-straight-power-10-psu.html
I have had this in for about 3 days now and luckily don't get any hiss or audible noise from the bequiet psu. The difference is great :)
post edited by jakedude182 - 2015/02/04 14:10:22