Silent Running: Two Fanless Power Supplies And A Quiet One, Tested

Two Fanless Power Supplies, Compared

Given the number of massive CPU coolers and loud graphics cards that make their way through our lab, it's easy to overlook the noise coming from power supplies. In general, power supply fans are drowned out by other system components. Even a mechanical hard drive tends to be more noticeable than a nice, big 120 mm cooler lackadaisically blowing air through large vents in a PSU.

But just ask anyone who's been burnt by a cheap power supply, or someone who hasn't blown out their chassis in a couple of years: PSU fans can get really loud.

What if you simply want a super-quiet machine? A computer for the living room or bedroom, perhaps. There are such things as passively-cooled graphics cards. Even more effective, liquid cooling has the potential to draw heat away from your components and dissipate it using larger, slower-spinning fans that generate barely a whisper. Swap out that clacking hard drive for an SSD and really, there's not much left inside your PC to disrupt the glorious silence.

Well, almost. There's still the issue of that ever-turning power supply fan.

Today's energy-efficient power supplies waste less power as heat than they used to. However, they still require cooling. And of course, the easiest way to achieve that is with a fan. But there are passively-cooled power supplies without fans (and other models specifically equipped with low-noise fans) for applications that demand silence.

We grabbed three PSUs purportedly known for their acoustic qualities, hoping to find at least one worth recommending. Upon hearing our call for submissions, Seasonic and SilverStone each sent in a fanless model to test. The former gave us a look at its X-460, while the latter shipped off its SST-ST50NF. For the purposes of comparison, we grabbed a single fan-cooled unit that's supposed to be ultra quiet: be quiet!'s Straight Power E9 CM 480 W. Unfortunately, you can't get it in the U.S., so it's really serving as a point of reference here today.

It's also notable that none of these are designed to sustain more than 500 W of output. Higher-wattage power supplies generate more heat under load, even if they're very efficient. As a result, passive cooling generally isn't an option once you start looking at more enthusiast-oriented configurations.

  • amuffin
    Seasonic, me gusta :)
  • zeratul600
    Why does americans are so picky about the noise rate??? i never stop to think about that! it has never become an obstacle to enjoy my pc experience
  • the1kingbob
    Fan noise has never bothered me much, which maybe why I own two 4870s... one of which has a jet plane I mean reference cooler on it..... sadly my wife doesn't care much for the noise, which lead me to buy her wireless headphones :)

    I think it is quite neat that they have fanless option. I would never take the risk, but if I did I would chose seasonic, my 750W has done me well.
  • s3anister
    zeratul600Why does americans are so picky about the noise rate??? i never stop to think about that! it has never become an obstacle to enjoy my pc experienceLast time I checked, Americans aren't the only ones who enjoy a silent computing experience...
  • amuffin
    zeratul600Why does americans are so picky about the noise rate??? i never stop to think about that! it has never become an obstacle to enjoy my pc experienceMany companies that are focused on silence such as Noctua and beQuiet! are not "American."
  • Deemo13
    I didn't know they made fanless power beans.
  • uruquiora
    Seasonic for the win :)
  • mesab66
    ZERTUL600......FOR THE VAST MAJORITY OF FOLKS, PERSISTANT/RELENTLESS NOISE QUICKLY BECOMES VERY ANNOYING!!..........give 100 folk a choice of 2 pc rooms - one near silent and one, noisy as hell. Riddle me many go for the quiet room?
    --> argument over.
  • mitko
    A year ago I built a water cooled system with an i7 2600k and 2 x Radeon 6990. The whole point of the water cooling was to make things extra quiet, which it did, except for the power supply. I tried two different Corsair AX1200 units before switching to a Nexus RX1100. The power supply is still BY FAR the noisiest component in the computer. Does anyone have a suggestion how to reduce the noise? I could not find any currently manufactured water cooled PSUs. Do you think it is possible to use 2 low-noise PSUs to power components on the same motherboard? Any other ideas are also welcome. I need at least a 1100W PSU, as I've actually measured the power consumption to be 1067W at 100% CPU and GPU load.

    For the record I am not an American and I don't live in the US :)
  • belardo
    In a quality modern PSU... can anyone really hear the PSUs?

    I've been buying Corsair and even $45 Thermaltake 500... and I cannot hear them... with the cover open. The problems with FANLESS PSUs and GPUs is that they become heat-sinks... sure they are quiet, but everything around them gets warm. You need to blow the hot air out.

    Going from a fanless GPU to something with a huge fan (H.I.S. brand) - the fans barely makes noise and use a rear exhaust and I can run the system fans at a lower speed.

    Mitko: get soundproofing material, apply to inside of case. Put case on floor.

    My case is on the desk, a foot or so away from me... its no louder than the A/C vent blowing air in the room.