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Head-to-head · Best 850w Power Supplies

Corsair HX850 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.

The short answer

Corsair HX850 comes out ahead by a clear margin (4.6 vs 4.1). The gap is mostly about fit for purpose — read the strengths below before deciding.

Corsair HX850
Higher ratedRanked #1 in Best 850w Power Supplies
Corsair HX850

The Corsair HX850 is a high-performance power supply that delivers excellent efficiency and silent operation, particularly at low loads thanks to its ZeroRPM mode. Tom's Hardware praised its ability to maintain full power at 46°C and noted its superior noise reduction compared to competitors like the EVGA 850 G3 and Seasonic FOCUS PLUS. KitGuru highlighted its 80 Plus Platinum certification, fully modular design, and robust build quality. However, reviewers noted some drawbacks including OCP issues at 5VSB and bulky cable configurations. This PSU is ideal for enthusiasts seeking reliable, quiet power delivery but may not suit users prioritizing minimal cable clutter.

Strengths
  • — Full power at 46°C ambient temperature
  • — 90% efficiency at real-world load conditions
  • — ZeroRPM mode for fanless operation at low loads
Watch-outs
  • — OCP at 5VSB
  • — Bulky ATX, EPS and PCIe cables
Buy at ebay.comFull review →
Seasonic Focus PX-850
Ranked #7 in Best 850w Power Supplies
Seasonic Focus PX-850
$345as of Jul 8

The Seasonic Focus PX-850 is a high-quality 850W Platinum power supply that delivers excellent efficiency and reliability. Reviewers praised its fully modular design, high-grade Japanese capacitors, and Fluid Dynamic Bearing fan with customizable cooling modes. The unit offers a single +12V rail capable of 70A and comes with a 10-year warranty, setting it apart from competitors. While it's priced competitively at around $140, it remains more expensive than some budget alternatives. This PSU is ideal for enthusiasts and professionals seeking premium build quality and long-term reliability, though budget-conscious users might find better value elsewhere.

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 some budget alternatives despite being $20-$40 cheaper than competitors
  • — Small 140mm footprint may not fit all cases with tight space constraints
$345 · Check Price on AmazonFull review →

Specs side-by-side

SpecCorsair HX850Seasonic Focus PX-850
Wattage850W850W
Efficiency80 Plus Platinum80+ Platinum
Form FactorATXIntel ATX 12 V
ModularityFully ModularFully Modular
Fan Size135mm fluid dynamic bearing120mm FDB
Warranty10 years10 Years
Connectors2x EPS, 6x PCIe 6+2 pin, 16 SATA, 1x FDD, 1x ATX20+4Pin, 2 x 4/8 Pin CPU, 6 x 6+2 pin PCIe, 10 x SATA
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