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Scan code: LN65076 Manufacturer code: CP-9020083-UK

Corsair RMi Series 850W 80+ GOLD Full Modular Power Supply

850W Corsair RM850i, Full Modular, 80PLUS Gold, SLI/CrossFire, Single/Multi Rail, 70.8A, 135mm Fan, ATX PSU

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Scan code: LN65076 Manufacturer code: CP-9020083-UK
review 3xs Approved
End Of Life This product is no longer available to purchase
Delivery Options
  • By DPD to your specified address. | £5.48 Receive SMS with one-hour delivery window Weekend, timed and European delivery options are available at checkout

    Have your parcel delivered by DPD to your specified address. Receive SMS with one-hour delivery window

    Weekend, timed and European delivery options are available at checkout
  • Collect instore Collect from our Bolton store, BL6 6PE | Free

    Order online, collect from our Bolton store (25-28 Enterprise Park, Middlebrook, Horwich, Bolton, BL6 6PE)

  • UPS and DPD Pickup Pickup from local convenience store | £4.79

    Collect your parcel from your newsagents, petrol stations and convenience stores

  • SCANPROTECT Protect against installation damage for 28 days. More info

    ScanProtect is an enhanced warranty specifically designed and offered by Scan to reduce the risk of any mishap or damage to components during installation.

    Our aim with ScanProtect is to encourage our customers to upgrade or build their own PC confidently. For a small additional fee our customers are provided with complete peace of mind.

  • 48HR REPLACEMENT If you need to return this item, your replacement will be dispatched within 2 working days of your product arriving back at Scan. More info

RM850i - Corsair Power Supply - Fully Modular ATX PSU

Corsair RM850i Power Supply 80PLUS - Gold

Corsair RMi 850W Power Supply

This version of the RMi Series power supplies from corsair comes with a total power output of 850W. The RM850i gives you extremely tight voltage control with near quiet operation. The 80PLUS GOLD rating on this PSU reduces operating costs and excess heat. It also features a fully modular cable set, these DC cables makes building and upgrading your PC easier and leaves it looking great. The Zero RPM fan mode ensures virtual silence at low and medium loads. The RMi Series also features the Corsair Link Digital which makes it extremely easy to monitor the power supplies performance along with toggling single rail or multi rail modes, or controling fan speed directly from your desktop.

View other RMi power outputs:
RM650i - RM750i - RM1000i

Fully Modular Connectivity


RMi Fully Modular Cable Design

The fully modular design of the RMi power supply means that during your build you can mount the PSU in the case first and then attatch only the cables you need, making builds and upgrades easy with great looking results. In addition the advanced desktop app lets you monitor and log fan speed, voltages and power consumption, as well as control and configure +12V rail operation.

RM850i Efficiency & Noise Graphs


Efficiency Graph


Noise Graph

Corsair RM850i Output Power Chart

DC Output +3.3V +5V +12V -12V +5Vsb
Max Load 25A 25A 70.8A 0.8A 3A
Maximum Combined Wattage 150W 850W 9.6W 15W
Total Power: 850W
DC Output +3.3V +5V +12V1 +12V2 -12V3 +12V4 +12V5 +12V6 +12V7 -12V8 +12V +5VSB
Max Load 25A 25A 40A 40A 40A 40A 40A 40A 40A 40A 0.8A 3A
Maximum Combined 150W 850W 9.6W 15W
Total Power: 850W

Corsair RM850i Key Features

80PLUS - Gold

80 PLUS Gold CertifiedGold certification ensures high efficiency operation for less excess heat and lower operating costs.

Japanese Capacitors

Japanese 105°C capacitorsPremium internal components ensure solid power delivery and long term reliability.

Zero Fan Mode

Zero RPM Fan ModeFan doesn’t turn on until it’s needed, so you’ll enjoy virtually silent operation at low and medium loads.

10 Year Warranty

Configurable +12V RailIt’s your choice – run it in the default multi-rail +12V mode, or toggle single-rail operation.


Please note your statutory rights are not affected.

For further information regarding Scan's warranty procedure please see our terms and conditions

120 months
Return to base
RTB Period:
120 months
Manufacturer Contact Details
0871 472 4747
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850W Corsair RM850i, Full Modular, 80PLUS Gold, SLI/CrossFire, Single/Multi Rail, 70.8A, 135mm Fan, ATX PSU is rated 4.8 out of 5 by 15.
Rated 5 out of 5 by from Very quiet and solid built quality I have got for not long but so far Im very happy with the product. Very quiet and solid built quality
Date published: 2020-05-13
Rated 5 out of 5 by from Solid quality power supply Good power management and very quiet power supply. Great for a gaming PC and at this price point very good value. Good service from SCAN.
Date published: 2020-04-25
Rated 5 out of 5 by from Good quality, easy to install Love the fact that it's modular, makes it so easy to install and no extra wiring to have to 'lose '
Date published: 2020-03-30
Rated 5 out of 5 by from Perfect replacement for Corsair HX850W Professional Series I bought this to replace a Corsair HX 850W Professional Series, because the 24 pin ATX plug on the HX 850W had developed a bad connection in the plug that kept shutting the PC down. It took me a long time to find the source of the problem and I further damaged the wiring in the plug by wiggling it around to diagnose the problem. Unfortunately the ATX cable on the old HX850W is integrated into the Power Supply. I therefore needed to buy a new PSU. The RM850i was a perfect replacement and the cables are modular and plug into the PSU. ( If I have a cable problem again, I can just replace the cable). The RM850i was delivered on time, with every cable you could possibly want. My PC fired up perfectly after fitting it and the PSU is very quiet
Date published: 2020-02-16
Rated 5 out of 5 by from Reliable, Stable, Silent Good Price Stable voltages which don't fluctuate which is amazing. if you want to overclock. It seems like its a solid PSU since there's no whining or buzzing. Maybe they addressed some of the noise issues on these later models which have been mentioned in some previous reviews. The PSU fan has never run which is excellent, its asif its fanless. I did buy this whilst it was on offer which is a bonus. As for cables, they are a reasonable length for me just wish at least one of the SATA power connectors could be spaced further apart, so I can plug CD Drive and Hdd on the same cable, but we've all got specific issues which can't all be addressed as each person has their unique expectations. Yes the ends of the ATX CPU and GPU power connectors are sleeved with thick heat-shrink which makes it stiff so this can make it difficult to route these connectors and are a pain for cable management ordered on new years eve and got it the next day Ultimately very happy well worth spending a bit of extra money for something that will last many years.
Date published: 2020-02-06
Rated 5 out of 5 by from Excellent PSU Thus far it has worked supremely and I haven't had any problems with its operation. The installation wasn't without difficulties, however. One inconvenience was a complete lack of 'straight' SATA power connectors. All of them are 90 degree connectors, which is fine if there are drive mounting positions in your case that are horizontal. However, in my case, (Corsair 275R) SSD's can only be mounted vertically if you remove the drive bay in the bottom of the case, which I had to in order to accommodate the PSU cables. Trying to use a 90 degree connector was impossible without damaging the cable. You can easily purchase straight SATA connectors separately from Corsair, but I think it would be nice had they included even one cable. Another issue, but this is very dependent on your case and how good you are with cable management, but I found some of the cables to be a tad on the short side. Near the ends of the cables where the braiding stops, they are covered with heatshrink and a thick black adhesive underneath it. This made the ends of some cables very bulky and couldn't be put through some of my case's intended routing spots. It all worked out in the end, but there was a small element of hassle.
Date published: 2020-01-30
Rated 5 out of 5 by from Nice unit! My first time with a modular PSU. I am also bumping up from a 750W that I had before, as I had been having mysterious cut-outs and thought it could be down to the amount of draw on an ageing PSU. This seems to be performing just fine. I think it's helped by the new Ryzen chips requiring very little extra power. Fan is very low noise, which I like! I'm also rather impressed by the little bits bag they give you, because of course, you are very likely to have bits left over, so the bag helps to keep it all together. Only downside I'd say is that modular PSUs can be a bit confusing to hook up and know exactly what should plug in where, particularly when there are multiple banks of the same plug type, your mobo and GPU take various different plug types, and it doesn't explain whether there's a difference or if there's a strategy to it, like ideally having only one device per bank because they're on different rails or something (I don't know if that's even a thing).
Date published: 2020-01-30
Rated 5 out of 5 by from Excellent modular PSU The modular system is excellent and it comes supplied with a large array of cables for various uses.
Date published: 2020-01-04
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Is this good enough for a gaming PC

My old PSU has died it was a Corsair AX 850 would this be good enough for gaming? or would https://www.scan.co.uk/products/850w-corsair-rm850x-series-80-plus-gold-full-modular-sli-crossfire-single-rail-708a-plus12v-1x135mm- be better?
Asked by: Loateal
Works great in my gaming PC just built.
Answered by: fizziks
Date published: 2020-06-24
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Corsair RMi Series 850W 80+ GOLD Full Modular Power Supply
Corsair RMi Series 850W 80+ GOLD Full Modular Power Supply