Head-to-head · Best 850w Power Supplies

Corsair RM850e vs Seasonic Focus PX-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

Seasonic Focus PX-850 comes out ahead by a clear margin (4.2 vs 4.9). The gap is mostly about fit for purpose — read the strengths below before deciding.

Ranked #4 in Best 850w Power Supplies

Corsair RM850e

4.2

3 sources1 derived$119as of Jul 31

The Corsair RM850e is an affordable ATX 3.0 unit that performs solidly, with efficiency and a fully modular layout in its favor. Tech4Gamers reviewer Arsalan Shakil credited it with 'impressive efficiency and acceptable voltage regulation' even with non-Japanese capacitors and no native 12VHPWR connector. KitGuru's Allan 'Zardon' Campbell praised the quiet rifle-bearing fan and the soldering quality, but listed the 7-year warranty among the unit's shortcomings. That missing 12VHPWR connector is the catch for anyone running a high-end graphics card.

Strengths

— High efficiency with 90% efficiency rating
— Fully modular cabling for clean builds
— 7-year warranty for peace of mind

Watch-outs

— No native 12VHPWR connector for latest GPUs
— Uses non-Japanese capacitors

$119 · Check Price on Amazon Full review →

Higher ratedRanked #1 in Best 850w Power Supplies

Seasonic Focus PX-850

4.9

3 sources$413as of Aug 1

The Seasonic Focus PX-850 is a Platinum-rated 850W unit that runs efficiently and holds up over time. RelaxedTech praised the fully modular design, the high-grade Japanese capacitors, and the Fluid Dynamic Bearing fan with customizable cooling modes. A single +12V rail handles 70A, and the 10-year warranty puts it ahead of most competitors. At around $140 the price is competitive but still above budget alternatives. Enthusiasts and professionals who want premium build quality and long-term reliability should buy; budget-conscious users can find better value.

Strengths

— 80+ Platinum efficiency rating with 92% efficiency at 50% load
— Fully modular design with flat black cables for improved airflow
— Fluid Dynamic Bearing (FDB) fan with three operational stages: Fanless, Silent, and Cooling Mode

Watch-outs

— Price is still higher than budget Gold-class alternatives, even though it undercuts rival Platinum units by $20-$40
— Small 140mm footprint may not fit all cases with tight space constraints

$413 · Buy at newegg.ca 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.

Specs side-by-side

Spec	Corsair RM850e	Seasonic Focus PX-850
Wattage	850W	850W
Efficiency	ATX 3.0	80+ Platinum
Modularity	Fully	Fully Modular
Fan Size	120mm rifle bearing	120mm FDB
Form Factor	ATX Form Factor	Intel ATX 12 V
Warranty	Seven-year	10 Years
Compliance	80 PLUS Gold	Energy Star, RoHS, WEEE, ErP Lot 6, REACH
Connectors	—	20+4Pin, 2 x 4/8 Pin CPU, 6 x 6+2 pin PCIe, 10 x SATA

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