We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Rectangular ATX power supply unit with matte black finish and gold modular connectors visible on the front face

Seasonic

Seasonic PRIME GX-850 850W 80+ Gold Full Modular power supply

SKU CH-JM23-9GY3Q MPN PRIME GX-850

An 850 W full-modular ATX power supply with 80 Plus Gold efficiency, a single +12 V rail, six PCIe connectors and ten SATA connectors

  • TypeATX12V / EPS12V
  • Maximum Power850 W
  • Fans135mm Fluid Dynamic Bearing Fan
  • Main Connector20+4Pin
  • +12V RailsSingle
  • PCI-Express Connector6 x 6+2-Pin

Options ATX Gold (850W)

  • Stable power delivery with .5 % load regulation
  • Clean builds through full modular cabling
  • Lower running costs via 80 PLUS Gold efficiency
  • Silent operation with fanless mode up to 40 % load
  • Long-term reliability backed by 150000 hour MTBF

850 W full-modular ATX supply

The Seasonic PRIME GX-850 delivers 850 W of continuous power through a fully modular cable set. It uses a single +12 V rail rated at 70 A and holds 80 PLUS Gold certification for efficient conversion. The unit fits standard ATX12V and EPS12V bays with a depth of 170 mm.

Hybrid fan control and Japanese capacitors

A 135 mm fluid-dynamic-bearing fan runs in a semi-passive mode that stays off until the load reaches 40 percent. Users can toggle between S2FC and S3FC profiles with a rear switch to match their acoustic targets. Premium Japanese capacitors and micro-tolerance load regulation under .5 percent keep voltages steady.

Six PCIe connectors for multi-GPU builds

The supply provides six 6+2-pin PCIe plugs plus two CPU connectors and ten SATA leads. Gold-plated terminals reduce contact resistance on every cable. This connector count supports multi-GPU configurations without daisy-chaining adapters.

Highlights

  • Stable power delivery with .5 % load regulation
  • Clean builds through full modular cabling
  • Lower running costs via 80 PLUS Gold efficiency
  • Silent operation with fanless mode up to 40 % load
  • Long-term reliability backed by 150000 hour MTBF

Specifications

BrandSeaSonic
SeriesPRIME Ultra Gold
ModelPRIME GX-850 ( SSR-850GD)
TypeATX12V / EPS12V
Maximum Power850 W
Fans135mm Fluid Dynamic Bearing Fan
Main Connector20+4Pin
+12V RailsSingle
PCI-Express Connector6 x 6+2-Pin
SATA Power Connector10
Max PSU Length170 mm
ModularFull Modular
Energy-Efficient80 PLUS GOLD Certified
Over Voltage ProtectionYes
Input Voltage100 - 240 V
Input Frequency Range50/60 Hz
Input Current11 - 5.5A
Output+3.3V@20A, +5V@20A, +12V@70A, [email protected] , [email protected]
MTBF150,000 hours
ApprovalscTUVus, TUV, CB, CCC, BSMI, EAC, CE, Energy Star, RoHS, WEEE, ErP Lot 6, REACH
Connectors1 x Main Power (24/20 pins)
2 x CPU (8/4 pins)
6 x PCIe (8/6 pins)
10 x SATA
5 x Peripheral
1 x Floppy
Features80 PLUS Gold certified
Micro Tolerance Load Regulation (0.5 %)
Cable-free Connection Design
Premium Hybrid Fan Control - Fanless until 40 % load
Multi-GPU setup
Gold plated connectors
Dimensions6.69" x 5.91" x 3.39"
Shipping weight3.63 kg
Package size340 × 208 × 137 mm

Other versions of this model

5 more in the same range

Same family, different memory, cooler or clock — compare before you commit.

Questions about this item

How do I install the full-modular cables, and what is the common mistake?

Connect the 20+4 pin, CPU 8/4 pin, and up to six PCIe 6+2 pin cables only to the ports you need; the step people miss is leaving unused cables in the box instead of plugging every socket.

What maintenance or replacement will this PSU need later?

The 135 mm fluid-dynamic-bearing fan is the only moving part; after many years it may need cleaning or replacement, while the premium Japanese capacitors are rated for long life.

What limit appears first under sustained heavy load?

The single +12 V rail tops out at 70 A, so continuous draws near 850 W will hit the current ceiling before thermal protection engages.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.