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  • Corsair RM850x is a black and silver computer power supply unit. It is designed to provide power to a motherboard and its components, including SATA/PATA drives and PCIe slots. The unit has a 12V output and is capable of delivering up to 850 watts of power. The Corsair RM850x is a reliable and high-quality power supply for a wide range of computer systems.
  • Corsair RMx Series Power Supplies: Our Best-Selling Power Supplies, Updated. Fully Modular, Low Noise, and Cybenetics Gold-Certified for Reliable Power.
  • ATX 3.1 Certified: ATX 3.1 and PCle 5.1 compliant, ideal for delivering dependable power to current and future top-performing PCs. 100% Japanese 105C Electrolytic Capacitors. ATX 3.1 PCle 5.1 with 12V-2x6.
  • Fully Modular Connectors: SATA/PATA SATA PATA OSI338v0 Connect only what you need using sleek embossed cables with low-profile combs to make installations a breeze. 1x CPU/PCIe / CPU PCIe 12V-2x6 Native 12V-2x6 GPU cable included for use with modern graphics cards such as the NVIDIA GeForce RTX 40 Series.
  • The image features a 140mm low-noise fan with a fluid dynamic bearing and magnetic dome structure that keeps noise to a minimum. The fan also has a Zero RPM mode, which eliminates fan noise completely at low to medium loads.
  • Get more air through the PSU or override the Zero RPM Mode and low-noise profile of the RMx series with our manual fan override knob, increasing fan speed and airflow.
  • FULLY MODULAR CABLING Connect only the cables you need. 1x ATX (24-pin) 2x ATX 12V (4+4-pin) 3x PCIe (6+2-pin) 1x 12V-2x6 (12+4-pin) 2x 4 SATA (Straight) 1x 3 PATA (4-pin)
  • WORLD-CLASS 24/7 CUSTOMER SUPPORT O COUNTRY LOCAL CORSAIR 10 GUARANTED REGULATIONS YEARS ARE APPLICABLE WORLD-CLASS SUPPORT Our award-winning service means you can enjoy your gear worry-free.
  • CORSAIR X RM850x
  • CORSAIR RM850x
  • The text on the image reads "Corsair RM850x / CPU PCle a CUNDIGAT - NIONTO HYSOO SATA/PATA / SATA, AIL PATA nv ONLY MOTHERBOARD 12V-2x6."
  • Alt View 21. CORSAIR - RMx Series RM850x Cybenetics Gold Fully Modular ATX Power Supply - Black.
  • Alt View 22. CORSAIR - RMx Series RM850x Cybenetics Gold Fully Modular ATX Power Supply - Black.
  • Alt View 23. CORSAIR - RMx Series RM850x Cybenetics Gold Fully Modular ATX Power Supply - Black.
  • The text on the image reads: "MOTHERBOARD 12V-2x6 CPU PU/ PCle / SATA/PATA / PATA DESIGNED FOR USE WITH GENUINE CORSAIR TYPE 4 CABLE SETS ONLY."
  • Corsair RM850x
  • The image shows a variety of Corsair products, including a box and several cords. There are a total of 12 cords, with some of them being black and white. The cords are arranged in a row, and they are all connected to a single box. The box is placed in the middle of the scene, surrounded by the cords. The arrangement suggests that these cords are part of a larger electronic system or setup.

CORSAIR - RMx Series RM850x Cybenetics Gold Fully Modular ATX Power Supply - Black

Model:
CP-9020270-NA
SKU:
6587623
Highly rated by customers for:
Your price for this item is $169.99

Customer reviews

Rating 4.8 out of 5 stars with 268 reviews

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Rating by feature

  • Value

    Rating 4.6 out of 5 stars

  • Quality

    Rating 4.8 out of 5 stars

  • Ease of Use

    Rating 4.7 out of 5 stars

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There aren't enough negative mentions yet.
95%would recommend to a friend

Customers are saying

Customers commend the RMx Series RM850x Cybenetics Gold Fully Modular ATX Power Supply for its excellent overall performance, making computers run perfectly. The power supply also stands out due to its fully modular cables that simplify cable management and its impressively quiet operation, featuring a desirable zero fan mode. Furthermore, users appreciate the ease of installation and the substantial power capacity it provides.

This summary was generated by AI based on customer reviews.

The vast majority of our reviews come from verified purchases. Reviews from customers may include My Best Buy members, employees, and Tech Insider Network members (as tagged). Select reviewers may receive discounted products, promotional considerations or entries into drawings for honest, helpful reviews.
Page 4 Showing 61-80 of 268 reviews
  • Pros mentioned:
    Noise level, Overall performance

    Good quiet clean PSU

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    Posted . Owned for 3 months when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Extremely quiet, runs good with no visible issues. The fan knob is a little pointless as 99.9% of the time you will just leave it on automatic and it will only turn on when it's hot.

    I would recommend this to a friend
  • Pros mentioned:
    Cable management

    Good PSU

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    Posted . Owned for 3 weeks when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    My aging 1000W PSU was unstable with the 5070. Using this PSU, I didn't need to use adapters for the 12V-2X6 power connector. My computer is now perfectly stable. Works well. I've been trusting Corsair supplies for multiple builds for over a decade. Glad to upgrade to a modular power supply, too. Cleans up the case and improves airflow. Only downside is that the cables are not wrapped, but at this price point it wasn't expected.

    I would recommend this to a friend
  • Pros mentioned:
    Cable management

    Very nice

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    Posted . Owned for 2 weeks when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Easy to setup. Nice modular PSU & nicely labled cables. Wish there was a manual to explain what is what and where is for why.

    I would recommend this to a friend
  • Pros mentioned:
    Power supply capacity

    Powerhouse

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    Posted . Owned for 1 month when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    This PSU has no power issues at all. I run battlefield 6 with discord and other apps running and it doesn't break a sweat. And for the price its the perfect choice. Would buy again

    I would recommend this to a friend
  • Pros mentioned:
    Noise level, Overall performance

    Power supply

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    Posted .
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Great value power supply. Has been working very well for me. No coil whine or anything.

    I would recommend this to a friend
  • Pros mentioned:
    Cable management

    Reliable Power Supply

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    Posted . Owned for 3 weeks when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    The included cables are a cleaner design than older versions. The adjustable fan option is fine if you're worried about wear on the bearings with starting and stopping. Well tested and reviewed unit.

    I would recommend this to a friend
  • Pros mentioned:
    Power supply capacity

    Works as expected, easy to use

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    Posted .
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Plenty of power for all but the highest end graphics cards. Good modularity for easy installation

    I would recommend this to a friend
  • Pros mentioned:
    Noise level, Overall performance

    Power supply

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    Posted .
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Great product No noise Working fine so far I would strongly recommend it

    I would recommend this to a friend
  • Pros mentioned:
    Noise level, Power supply capacity

    Works perfect, even under heavy load

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    Posted . Owned for 3 months when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Overclocking a modern high end build has posed no issues for this PSU, and it runs very efficiently and silently.

    I would recommend this to a friend
  • Pros mentioned:
    Overall performance

    Corsair power supply

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    Posted .
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    This works great and the modular is a huge improvement from my original PSU.

    I would recommend this to a friend
  • Pros mentioned:
    Cable management, Overall performance

    Psu good quality

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    Posted . Owned for 1 month when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Works good so far. No issues. Like the make of the cables.

    I would recommend this to a friend
  • Pros mentioned:
    Overall performance
    Best Buy Employee

    Good features

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    Best Buy Employee
    Posted . Owned for 2 weeks when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Good psu no complaints would reccomend. It has a fan speed knob which is cool

    I would recommend this to a friend
  • Pros mentioned:
    Noise level, Power supply capacity

    Reliable and Easy PSU

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    Posted .
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Very quiet and reliable power delivery for my components, and easy to organize with the cords marked

    I would recommend this to a friend
  • Pros mentioned:
    Cable management, Noise level

    As usual, a quality psu from corsair

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    Posted . Owned for 3 months when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    zero fan mode is awesome. Has all the power cables I could ever need and then some. Nice to see they finally left the rubber coated wires in the past and started offering some cable combs as well.

    I would recommend this to a friend
  • Pros mentioned:
    Noise level, Power supply capacity

    Great quality and performance

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    Posted .
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Really good power supply with more than enough power to run my 5070 and ryzen 9 5950x. Runs quite and couldnt ask for more out of a quality power supply

    I would recommend this to a friend
  • Pros mentioned:
    Power supply capacity

    Excellent Upgrade

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    Posted .
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    I upgraded most of my PC components about a year and a half ago (Motherboard, Processor, Graphics Card, Memory, PC Case) but reused my old 750 power supply which wasn't fully modular. I decided to get this 850 fully modular power supply for the added flexibility and to have some extra power for my components and it has worked flawlessly so far. Great product!

    I would recommend this to a friend
  • Pros mentioned:
    Cable management

    RM850x Working Great and Great Deal

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    Posted . Owned for less than 1 week when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    I Haven't put this power supply to the longevity test yet. However, I have loaded it up quite well at this point. It seems to be great so far. It has an adjustable fan and modular cable design is great. It should have all of the cables you may need.

    I would recommend this to a friend
  • Pros mentioned:
    Noise level

    Above expectations

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    Posted . Owned for 2 months when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Functioning perfectly, and quiet. First time using a component based PSU and love the flexibility and cable reduction in my case. Would definitely buy again.

    I would recommend this to a friend
  • Pros mentioned:
    Cable management, Overall performance

    solid power supply

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    Posted . Owned for 3 weeks when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    solid power supply reliable as you can get and comes with good quality cables.

    I would recommend this to a friend
  • Pros mentioned:
    Overall performance, Power supply capacity

    Quality power supply.

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    Posted . Owned for 1 month when reviewed.
    This reviewer received promo considerations or sweepstakes entry for writing a review.

    Great power supply. More than enough power for my custom build. Corsair makes quality products. Performs great.

    I would recommend this to a friend
Page 4, Showing 61-80 of 268 reviews
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