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
*Price sourced from Amazon.com. Last updated 2026-07-09. 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 $219.99. Read recent reviews carefully before committing.
Corsair RM850x series power supplies are built with the highest quality components to deliver 80 PLUS Gold efficient power to your PC. Using only Japanese 105 Degree C capacitors, users can depend on an RM850x PSUs' long life and reliability, backed by a ten year warranty. Zero RPM Mode means an RM850x series PSU is virtually silent at low and medium loads, and even at maximum power, a low noise fan ensures quiet operation. Fully modular cables make PC builds and upgrades easy, as you only need to install the cables your system requires. Quiet, efficient and dependable, an RM850x PSU has…
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
| Brand | Corsair |
|---|---|
| Wattage | 850 watts |
| Fan Size | 135 Millimeters |
| Model Name | RMx |
| Form Factor | ATX12V |
| Model Number | CP-9020180-NA |
| Connector Type | ATX, EPS |
| Cooling Method | Air |
| Item Type Name | Computer Power Supply |
| Number of Fans | 1 |
| Output Wattage | 850.0 |
| Item Dimensions | 6.3 x 5.91 x 3.39 inches |
| Mfr Part Number | CP-9020180-NA |
| Compatible Devices | Personal 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.
*Price sourced from Amazon.com. Last updated 2026-07-09. Price and availability subject to change.
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