Corsair CS850M 850W Power Supply Review

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Packaging, Contents, Exterior And Cabling

Packaging

The CS850M comes in a small package with a touch of a pale green that points to the unit's eco-friendly orientation. Most of the real estate on the front of the box is taken by a photo of the PSU's fan, with Corsair's logo at the center. At the top-right corner is the series description along with the word "modular," which describes an important feature that is highly desired by many enthusiasts from today's PSUs. On the bottom-right side is the model name, and on top there are three icons drawing attention to the 80 PLUS Gold efficiency, three-year warranty and ErP Lot 6 compliance, which is required for every PSU sold in the EU zone.

On the back of the box we find detailed info about the product. In this case, Corsair provides a description of the available connectors along with cable lengths. There are also two graphs depicting the fan’s operation curve and the efficiency of the PSU with 115/230VAC inputs. Finally, near the bottom-right corner, you will find the power specifications table.

On top of the box there is a multilingual list that includes the power input specs, compatibility with the ATX12V and EPS12V standards and the PSU's dimensions. On the right side, a chart conveys all of Corsair's power supply families, classifying them from top to bottom. As you can see, the company has nine lines covering almost every possible segment.

Contents

The unit is well protected by packing foam inside the box, ensuring that even if shipping conditions are harsh, the product will reach your hands in good condition. The bundle includes a warranty leaflet along with the user's manual, a set of fixing bolts, some zip-ties for cable management, an AC power cord and the modular cables.

Exterior

Corsair's finish quality is decent, though its design is plain and rather boring. Only the highest-end Corsair PSUs feature a nice fan grill that distinguishes them from the competition. At the CS850M’s front, a small on/off switch is located under the AC receptacle, while the fan grill uses a familiar honeycomb design. Two small decals grace the sides, and a power specification label is located on the bottom.

The modular panel has only six sockets: two for the PCIe leads and the rest for peripheral cables. I’d prefer a fully modular design, though that would affect the product's final price. Fortunately, the fixed cables cover essential connections. It's the combination of flat and and stealth EPS cables with round and colored ATX cables that looks strange to me. To give you an idea how compact the CS850M is, its 140mm fan occupies most of the PSU's top panel.

Cabling

As noted, the only non-stealth cable is the main ATX cable. We have to wonder why Corsair didn’t bother providing some darkened wires there as well.

All of the modular cables are flat, which proves convenient during the installation process. Ribbon cables are easier to route inside of a chassis. On top of that, they block less airflow compared to conventional cables.

Contributing Editor

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, 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