Corsair CS850M 850W Power Supply Review

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Cross-Load Tests And Infrared Images

To generate the following charts, we set our loaders to Auto mode through our custom-made software before trying over a thousand possible load combinations with the +12V, 5V and 3.3V rails. The load regulation deviations in each of the charts below were calculated by taking the nominal values of the rails (12V, 5V and 3.3V) as point zero.

Our cross-load tests are described in detail here.

Load Regulation Charts

We found tight load regulation on the +12V rail, especially for a PSU that doesn’t address the enthusiast crowd.

Efficiency Chart

Efficiency throughout most of the unit’s operating range is constantly above 85 percent, and there is a pretty large region with efficiency that exceeds 90 percent.

Ripple Charts

Ripple on the +12V rail spikes to the 40–60mV region only when the PSU is pushed close to its limits. Of course, we'd prefer if it stayed below 40mV, but we can’t expect too much from this platform since it doesn’t use any Japanese capacitors on the secondary side. Ripple on the minor rails is controlled well, even at high loads. On the 5VSB rail, ripple suppression is excellent.

Infrared Images

We took some photos of the PSU during the end of the cross-load tests with our modified FLIR E4 camera, which delivers 320x240 IR resolution (76,800 pixels).

Aris Mpitziopoulos
Contributing Editor

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

  • codygriffy
    Looks very nice!
    Reply
  • Shneiky
    Another CS PSU with bad caps and short life. And at 120 USD or more than 120 EUR as it appears in my district, this PSU does not stand a chance against the competition. Still a lot of people will buy it just because it has a Corsair name on it. I feel kinda bad that Corsair ruins their legacy of quality with products like CS and VS.
    Reply
  • giantbucket
    15746324 said:
    Another CS PSU with bad caps and short life. And at 120 USD or more than 120 EUR as it appears in my district, this PSU does not stand a chance against the competition. Still a lot of people will buy it just because it has a Corsair name on it. I feel kinda bad that Corsair ruins their legacy of quality with products like CS and VS.

    and then there are people who are going to hate on it just because it has a Corsair name on it...
    Reply
  • ykki
    Nice review! Can Tom's start a psu rating system (on a scale of 1 to 10)?
    Reply
  • Amdlova
    this perform really bad
    Reply
  • endeavour37a
    ykki, here is a tier list of PSUs, perhaps this is what your talking about.......
    http://www.tomshardware.com/forum/id-1804779/power-supply-unit-tier-list.html
    Reply
  • Sakkura
    Breaks ATX spec, high-ish 12V ripple, bad capacitors... No thanks.
    Reply
  • Shneiky
    ykki,

    I do not hate Corsair products because they are Corsair. I have a Corsair K70 and I love it. What I hate is cheaply made equipment that wants a price premium because it is X brand.
    Reply
  • Aris_Mp
    @ykki The relative performance graph can play this role and with much more accuracy. However it measures pure performance and doesn't take into account other factors as output noise, warranty period etc. For these factors a final rating is needed, indeed.
    Reply
  • damric
    Good review, Aris.

    I see no reason to buy this PSU when there are other good units with lower price built with better components. Example: Many XFX (Seasonic) and Golden Green (Capstone/B2) cost less but are more reliable with all good caps. Unfortunately, most consumers will be suckered in by the Corsair sticker.

    On the bright side, these Great Wall units have far less problems than the CX series. Probably even more reliable than the RM.
    Reply