Corsair

Corsair RMX Series

Status: Corsair RMX Series: Unavailable on Amazon as of 2026-10-20 22:16 UTC. SpecPicks has no in-stock listing with matching specs on file; the search below lists current offers. eBay sellers may still list this model new or used.

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Bottom line: The Corsair RMX Series: Ten-year warranty covers multiple GPU upgrade cycles; main trade-off: no iCUE compatibility, so no software fan or wattage monitoring.

Unavailable on Amazon as of 2026-10-20 22:16 UTC

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Currently unavailable on Amazon. Not the same product — 3 in-stock alternatives:

Similar: ALIMENTATIONS Corsair 601-850 Watt RM850X 850W… — $218.00 on Amazon as of 2026-10-21 10:13 UTC (price may vary).

View Current Price — $218.00

Similar: Corsair RMX Series — $129.10 on Amazon as of 2026-10-21 12:15 UTC (price may vary).

View Current Price — $129.10

Similar: Redragon RGMS-850W PRO 80+ Gold 850 Watt Power… — $74.99 on Amazon as of 2026-10-21 12:20 UTC (price may vary).

View Current Price — $74.99

Original listing (currently unavailable) → Compare to similar power supplies

By Mike Perry, Founder & Editor-in-Chief · Listing data updated 2026-10-20

Mike Perry — Hardware researcher since 2014, focused on GPU performance across gaming, rendering, and local-LLM inference. Synthesises community benchmarks, manufacturer specs, and public forum data into actionable buying guides. About the author →

Pros & Cons

Pros

✓ Ten-year warranty covers multiple GPU upgrade cycles
✓ Zero RPM Fan Mode leaves the fan stopped at low and medium loads
✓ 100% Japanese 105C capacitors rated industrial grade throughout
✓ Continuous 850W output rated at 50C ambient, not a 25C best case

Cons

✗ No iCUE compatibility, so no software fan or wattage monitoring
✗ Not Modern Standby compatible — a factor for some newer motherboards
✗ Fully modular cables ship as flat ribbons, adding sleeving cost for show builds
✗ 850W ceiling limits headroom for dual-GPU or heavily overclocked HEDT builds

Manufacturer description

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 tunnel. Continuous output is rated at 50 degrees C ambient, not the optimistic 25 degrees C some supplies quote. Fully modular cables mean you install only what your…

SpecPicks Verdict

SpecPicks scored Corsair RMX Series using a rating × review-volume × price-fit model applied to published specs and reviews across the power supplies category. Corsair's power supplies lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.

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 retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.

Frequently Asked Questions

Is 850W enough for an RTX 4090 or 5090 build?

The RM850x delivers a continuous 850W rated at 50C ambient, which covers a single high-end GPU paired with a mainstream CPU. Check your specific GPU maker's recommended PSU wattage before buying, since transient spikes vary by card.

How long is the Corsair RM850x warranty?

Corsair backs the RM850x with a ten-year warranty. Confirm current registration and coverage terms on the product listing, as warranty policies can vary by region.

Does the fan run all the time?

No. Zero RPM Fan Mode keeps the fan fully stopped at low and medium loads, so the unit is silent during desktop work and light gaming. The 5.3-inch low-noise fan only spins up as load climbs.

Is the RM850x fully modular or semi-modular?

Fully modular. Every cable detaches, including the 24-pin, so you install only the connectors your build actually uses — helpful for airflow in a compact case.

Does the RM850x work with Corsair iCUE software?

No. Corsair lists iCUE Compatibility as No for this unit, and it is also not Modern Standby compatible. You get 80 PLUS Gold efficiency and Zero RPM operation without any software layer.

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	13.5 centimeters
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
Item Dimensions	6.3 x 5.91 x 3.39 inches
Mfr Part Number	CP-9020180-NA
Compatible Devices	Personal Computer
Connector Quantity	36
Power Supply Design	Full Modular
Warranty Description	10 years warranty
Maximum Input Voltage	120 volts_of_alternating_current
Minimum Input Voltage	100 volts_of_alternating_current
Item dimensions L x W x H	6.3 x 5.91 x 3.39 inches
Full listing title	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

Ready to buy?

Amazon shows no buyable offer for Corsair RMX Series at the last check. A similar in-stock product is ALIMENTATIONS Corsair 601-850 Watt RM850X 850W…. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.

View Similar — $218.00