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Corsair RMX Series, RM850x, 850 Watt, 80+ Gold Certified, Fully Modular Power Supply (Low Noise, Zero RPM Fan Mode, 105°C Capacitors, Fully Modular Cables, Compact Size) Black
Corsair

RMX Series, RM850x, 850 Watt, 80+ Gold Certified, Fully Modular Power Supply (Low Noise, Zero RPM Fan Mode, 105°C Capacitors, Fully Modular Cables, Compact Size) Black

By SpecPicks Editorial · Verified 2026-08-23

$139.99
Buy on Amazon — $139.99 Compare to similar power supplies

*Price sourced from Amazon.com. Last updated 2026-08-23. Price and availability subject to change.

Bottom line: The RMX Series, RM850x, 850 Watt, 80+ Gold Certified, Fully Modular Power Supply (Low Noise, Zero RPM Fan Mode, 105°C Capacitors, Fully Modular Cables, Compact Size) Black is a niche pick — read recent reviews before buying in the power supplies category, priced around $139.99. Read recent reviews carefully before committing.

Corsair's RM850x delivers 850 watts of 80 PLUS Gold-certified power to your PC, and the spec sheet explains why it holds a 4.8 out of 5 rating across 13,071 reviews. Every capacitor inside is a 100 percent industrial-grade, 105 degree C Japanese unit, and the whole supply is backed by a ten-year warranty — the kind of coverage that outlasts two or three GPU upgrades. Zero RPM Fan Mode keeps the 5.3-inch fan completely stopped at low and medium loads, so your build stays silent until you actually push it; at maximum draw the low-noise fan takes over without turning your case into a wind…

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SpecPicks Verdict

SpecPicks classifies Corsair RMX Series, RM850x, 850 Watt, 80+ Gold Certified, Fully… as a niche pick — read recent reviews before buying in the power supplies category, based on our editorial and benchmark analysis and our ranking model that weights rating × review-volume × price-fit. Corsair's positioning sits within the broader category mid-tier. Use the Compare tool to put it side-by-side with two or three close alternatives before clicking through to Amazon.

Common buyer scenarios for power supplies of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the Amazon listing before purchase. Prices, stock, and Prime eligibility update directly from Amazon's catalog and may have moved since this page was last verified.

Pros & Cons

Pros

  • ✓ 80 Plus Gold certified for lower power consumption, less noise and cooler temperatures
  • ✓ Backed by Corsair's warranty and support channels
  • ✓ Ships via Amazon with Prime eligibility and the standard returns policy

Cons

  • ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
  • ✗ Price, stock, and Prime eligibility update from Amazon and may have changed since this page was last verified

Key Features

  • 80 Plus Gold certified for lower power consumption, less noise and cooler temperatures
  • For maximum cooling surface area and performance
  • Zero RPM fan mode for near silent operation at low to medium loads; Continuous output rated temperature: 50°C
  • 100 percent industrial grade, 105°C rated Japanese capacitors ensure unwavering power and reliability
  • Fully modular cables, so you only connect the cables your system needs. Fan size-5.3 inches iCUE Compatibility-No. Modern Standby Compatible- No

Full Specifications

BrandCorsair
Wattage850 watts
Fan Size13.5 centimeters
Model NameRMx
Form FactorATX12V
Model NumberCP-9020180-NA
Connector TypeATX, EPS
Cooling MethodAir
Item Type NameComputer Power Supply
Number of Fans1
Output Wattage850
Item Dimensions6.3 x 5.91 x 3.39 inches
Mfr Part NumberCP-9020180-NA
Compatible DevicesPersonal Computer

Ready to buy?

Corsair RMX Series, RM850x, 850 Watt, 80+ Gold Certified, Fully Modular Power Supply (Low Noise, Zero RPM Fan Mode, 105°C Capacitors, Fully Modular Cables, Compact Size) Black is available on Amazon with Prime shipping and the full Amazon returns policy. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.

Check price on Amazon →

*Price sourced from Amazon.com. Last updated 2026-08-23. Price and availability subject to change.

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Corsair RMX Series, RM850x, 850 Watt, 80+ Gold Certified, Fully Modular Power Supply (Low Noise, Zero RPM Fan Mode, 105°C Capacitors, Fully Modular Cables, Compact Size) Black
$139.99
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