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

be quiet! Straight Power E9 CM 480 W

Our German team tested be quiet's Straight Power E9 CM 580 W in a previous round-up. That's this unit's bigger brother. The company claims that they're both the quietest models it sells. Although you can't buy the Straight Power here in the U.S., we're using it as a control, since its 480 W rating sits right between Seasonic's 460 W and SilverStone's 500 W specifications.

As far as specs go, be quiet's 480 W offering is only slightly different from its 580 W effort. It employs four +12 V rails, each supplying up to 18 A, and a modular cabling system with long, sleeved power cords. The number of receptacles on the power supply is more than ample for the systems a 480 W PSU might drive. In fact, it includes enough connectors for up to two graphics cards in SLI or CrossFire.

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be quiet! Straight Power E9 CM 480 W
AC Input100-240 V, 50-60 Hz
DC Output+3.3 V+5 V+12 V (#1)+12 V (#2)+12 V (#3)+12 V (#4)-12 V+5 Vsb
24 A22 A18 A18 A18 A18 A0.3 A3.0 A
Individual Output15 W3.6 W
Rail UtilizationSysSysCPU And VGA
Combined Output130 W456 W
Total Continuous Output480 W
Peak Output550 W
  • amuffin
    Seasonic, me gusta :)
    Reply
  • 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
    Reply
  • 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.
    Reply
  • 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...
    Reply
  • 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."
    Reply
  • Deemo13
    I didn't know they made fanless power supplies....cool beans.
    Reply
  • uruquiora
    Seasonic for the win :)
    Reply
  • 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 this....how many go for the quiet room?
    --> argument over.
    Reply
  • 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 :)
    Reply
  • 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.
    Reply