Head-to-head · Best 850w Power Supplies

Corsair RM850e vs Seasonic Focus GX-850

Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.

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The short answer

Corsair RM850e comes out ahead by a clear margin (4.1 vs 3.0). Corsair RM850e is best for: Budget-conscious builders wanting modular design and 12V-26 support. Read the strengths below before deciding.

Higher ratedRanked #3 in Best 850w Power Supplies

Corsair RM850e

4.1

2 sources$115.99as of Oct 21

The Corsair RM850e delivers reliable performance as part of Corsair's new RM series, offering fully modular cabling and native 12V-26 connectors for modern GPU support. Reviewers noted its efficient Cybenetics Gold-Certified design and quiet operation with zero RPM fan mode. While it provides solid power delivery and build quality, it trails competitors in warranty length, though KitGuru found only a £10 UK price difference over the 750W model. This PSU suits enthusiasts seeking a balance of efficiency and reliability without the premium warranty of flagship models.

Strengths

— Fully modular cabling allows for clean and customizable builds
— Native 12V-26 connector supports latest high-end graphics cards without adapters
— Efficient Cybenetics Gold-Certified design delivers up to 90% efficiency

Watch-outs

— KitGuru notes the 7-year warranty falls short of leading competitors' 12-year warranties

$115.99 · Check Price on Amazon Full review →

Ranked #7 in Best 850w Power Supplies

Seasonic Focus GX-850

3.0

1 sourceall derived$159.99as of Oct 21

The Seasonic Focus GX-850 is a compact, fully modular 850W power supply designed for modern systems with ATX v3.1 and PCIe 5.1 support. It features a 10-year warranty and efficient operation with 80+ Gold certification. However, some users have reported fan noise issues, particularly under light load gaming conditions. This PSU is ideal for mid-tower builds and high-performance systems requiring reliable power delivery.

Strengths

— Fully modular design with 80+ Gold efficiency
— Compact dimensions (140mm depth) suitable for mid-towers, per HWBusters
— 10-year warranty support

Watch-outs

— May be too loud during GPU-intensive tasks

$159.99 · Check Price on Amazon Full review →

Derived means the reviewer published no score, so one was inferred from their written verdict. Everything else is a number the publisher printed. How we rank.

How they stack up

Corsair RM850e

The Corsair RM850e offers a more affordable entry point into the RM series compared to the RM850x, but lacks the 10-year warranty and fluid dynamic bearing fan. It's less efficient than the EVGA SuperNOVA 850 G7 and doesn't match the premium build quality of the be quiet! Dark Power Pro 12 850W, though it does provide native 12V-26 support like the latter.

Seasonic Focus GX-850

The Seasonic Focus GX-850 is more compact than the Corsair RM850x but suffers from excessive fan noise under light loads, unlike the Corsair's fluid dynamic bearing fan. It matches the EVGA SuperNOVA 850 G7 in 10-year warranty and efficiency, but lacks the latter's Japanese capacitors and superior fan control features.

Specs side-by-side

Spec	Corsair RM850e	Seasonic Focus GX-850
Wattage	850W	850W
Efficiency	80 Plus Gold (up to 90%)	80+ Gold
Modularity	Full Modular	Fully modular
Fan Type	120mm rifle bearing with zero RPM mode	135mm Fluid Dynamic Bearing Fan
Warranty	7 years	10-year
Connectors	Fully modular with 12V-26	2x EPS, 3x PCIe 6+2 pin, 1x PCIe 12+4 pin, 8x SATA, 3x 4-pin Molex
Dimensions	140 x 150 x 86 mm	150 mm x 85 mm x 140mm
Form Factor	ATX 3.1	Compact

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