How We Test Power Supply Units

It is hard to conduct proper acoustics measurements on a PSU since you have to isolate it from the loaders; they are too noisy and interfere with the readings. However, moving the loaders far away from the test PSU requires long connection cables, which incur increased resistance. Power losses become significant in that case.

Thankfully, we found a way around these issues. With the help of a fully-featured hemi-anechoic chamber, we can conduct accurate sound measurements using a Class 1 Sound Analyzer.

We measure the fan's noise from one meter away. The noise measurements are conducted with a Class 1 Bruel & Kjaer 2250-L G4 Sound Analyzer, equipped with a type 4955-A low-noise and free-field microphone which can measure down to 5 dB(A). We also have a type 4189 microphone with a 16.6-140 dBA-weighted dynamic range. The sound analyzer is installed into a hemi-anechoic chamber, allowing for lower than 6 dB(A) ambient noise. A Bruel & Kjaer Type 4231 is used to calibrate the sound analyzer before every noise measurement.

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Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a contributing editor at Tom's Hardware, covering PSUs.

  • JPNpower
    Nobody can fault you guys for not being thorough enough! All we can wish for is that you do these tests a bit more often. I'm at a loss how to navigate the PSU field, and a "Best Picks" section for PSU's would be tremendously helpful.
    Reply
  • Nuckles_56
    Really good article, it is now nice and clear how you guys go and test the power supplies, and as JPNpower said, no one can fault you guys for not being thorough enough.
    Reply
  • ykki
    @JPNpower= I also think a best psu for the money article would be nice but the power supplies in the market pretty much stay the same. We may go for months before seeing any change in the list.
    Reply
  • Kewlx25
    Interesting!
    Reply
  • damric
    Looks legit, Aris.

    THW used to be the laughing stock of PSU reviews, but your recent reviews have changed all of that.

    Keep up the good work!
    Reply
  • damric
    Nobody can fault you guys for not being thorough enough! All we can wish for is that you do these tests a bit more often. I'm at a loss how to navigate the PSU field, and a "Best Picks" section for PSU's would be tremendously helpful.
    @JPNpower= I also think a best psu for the money article would be nice but the power supplies in the market pretty much stay the same. We may go for months before seeing any change in the list.

    I'll make one and submit it through bb-71 to get stickied.
    Reply
  • ykki
    15570872 said:
    I'll make one and submit it through bb-71 to get stickied.

    OK. If someone makes a psu list I'd rather see it from you (or the mods). Good luck.
    Reply
  • damric
    15570891 said:
    15570872 said:
    I'll make one and submit it through bb-71 to get stickied.

    OK. If someone makes a psu list I'd rather see it from you (or the mods). Good luck.

    It will be a group effort for sure :)
    Reply
  • iam2thecrowe
    It would be nice if all manufacturers could do this testing and publish results when they build the things, or even better for it to be a requirement. Then at least there would be less junk PSU's on the market.
    Reply
  • ykki
    15571045 said:
    It would be nice if all manufacturers could do this testing and publish results when they build the things, or even better for it to be a requirement. Then at least there would be less junk PSU's on the market.
    Or more fake reviews.

    Reply