Seasonic CORE GC-850 850W 80 Plus Gold ATX 3.1 PSU Black
Seasonic
Seasonic CORE GC-850 850W 80 Plus Gold ATX 3.1 PSU Black
The Seasonic CORE GC-850 850W 80 Plus Gold ATX 3.1 PSU is built for PC builders who want a reliable, quiet, and efficient power supply that is ready for the latest GPU standards. It addresses the need for modern PCIe 5.1 compatibility without sacrificing backward compatibility, thanks to both a 12V-2×6 connector and traditional 8-pin PCIe cables. A 5-year warranty and Seasonic's established engineering back it up for long-term builds.
Why this product
80 PLUS Gold efficiency cuts heat and costs
The 80 PLUS® Gold certification means a high proportion of drawn electricity is converted to usable power, reducing heat output and lowering electricity bills over the life of the build.
ATX 3.1 and PCIe 5.1 ready out of the box
It meets ATX 3.1 requirements and ships with a 12V-2×6 PCIe Gen 5.1 cable, making it compatible with the current generation of high-power graphics cards without needing an adapter.
Backward compatible with older GPUs
Two 8-pin PCIe connectors are included, so builders upgrading their PSU can keep an existing previous-generation graphics card without any additional cables.
Quiet 120 mm HDB fan with smart control
The Hydro Dynamic Bearing fan and Smart and Silent Fan Control (S2FC) adjust fan speed to load conditions, keeping noise low during everyday use.
Comprehensive protection suite
It includes OCP, OVP, UVP, OPP, SCP, and OTP protections to guard connected components against electrical faults.
5-year warranty for long-term confidence
Seasonic backs this unit with a 5-year warranty, reflecting the expected service life of a quality PSU in a primary build.
- Total Output850 W
- Efficiency80 PLUS® Gold
- ATX StandardATX 3.1
- PCIe Connector1× 12V-2×6 (PCIe Gen 5.1)
- ModularNon-Modular (Fixed Cables)
- Fan120 mm HDB
- Warranty5 Years
- Dimensions (W × H × D)150 × 86 × 140 mm
- SKUSEA-725
- EAN4711173879114
- Compatible with ATX 3.1 motherboards and cases via the 20+4 pin ATX connector.
- Supports PCIe 5.1 GPUs through the included 12V-2×6 (16-pin) connector.
- Works with previous-generation GPUs using the included 2× 8-pin PCIe cables.
- Accepts universal AC input from 100–240 V at 50/60 Hz, suitable for use worldwide.
- Non-modular design: all cables are fixed and cannot be removed, so cable management space inside the case should be considered before purchase.
- Only 2 SATA power connectors and 2 Molex connectors are provided; builds with many storage drives or legacy peripherals may require additional adapters.
Best for
- New GPU builds: the included 12V-2×6 PCIe Gen 5.1 cable means no adapters are needed for current high-end graphics cards.
- Noise-sensitive environments: S2FC and the HDB fan keep the unit quiet under moderate loads, suited to home offices or living-room builds.
- Mid-to-high-end gaming and workstation builds: 850 W with a 70 A +12V rail supports demanding CPU and GPU combinations.
- Global use: the 100–240 V universal input makes it suitable for builders in any region.
- Long-term builds: a 100,000-hour MTBF rating and 5-year warranty are suited to builders who do not want to revisit their PSU choice soon.
Trade-offs
- Builds with many storage devices: only 2 SATA power connectors are provided, which limits large multi-drive configurations without adapters.
- Small form-factor cases: at 150 × 86 × 140 mm, it is a standard ATX size and will not fit SFX or compact enclosures.
- Clean-cable or minimal-cable builds: fixed, non-modular cabling means all cables are always present in the case, regardless of how many are used.
- Very low-power systems: an 850 W unit in a light-duty PC represents over-provisioning that may reduce efficiency at minimal loads.
With 80 PLUS® Gold efficiency, Smart and Silent Fan Control (S2FC), and a 120 mm HDB fan, it ensures cool, quiet, and stable operation. The CORE GC-750 and CORE GC-850 include a 12V-2×6 PCIe Gen 5.1 cable, ready for the latest GPUs, while the CORE GC-650 meets all ATX 3.1 requirements with traditional connectors. Built on decades of engineering excellence, the CORE GC Series delivers the quiet efficiency, reliability, and durability that define every Seasonic power supply.
The 80 PLUS® Gold certification indicates that a high percentage of the electricity is converted into useful power, therefore there is less heat lost and more money saved on the electricity bill.
To ensure compatibility with older GPUs, the CORE GC ATX 3.1 includes a 2× 8-pin PCIe cable. It delivers reliable power up and works seamlessly with graphics cards from previous generations. This cable makes it easy to upgrade your PSU without needing to replace your GPU.
General
| Brand | Seasonic |
|---|---|
| Model | CORE GC-850 ATX 3.1 |
| MPN | SRP-CGC851-A5A32SF |
| Colour | Black |
| Warranty | 5 Years |
| Weight | 2.54 kg |
| Dimensions (W × H × D) | 150 × 86 × 140 mm |
Power & Efficiency
| Total Power Output | 850 W |
|---|---|
| Efficiency Certification | 80 PLUS® Gold |
| ATX Standard | ATX 3.1 |
| PCIe Standard | PCIe 5.1 |
| Max Output Current +12V | 70 A |
| Max Output Current +3.3V | 20 A |
| Max Output Current +5V | 20 A |
| Max Output Current +5Vsb | 2.5 A |
| Max Output Current -12V | 0.3 A |
| AC Input Voltage | 100 – 240 V |
| AC Input Frequency | 50 / 60 Hz |
| Input Current | 11 – 5.5 A |
| Operating Temperature | 0 – 50 °C |
| MTBF | 100,000 h |
Cooling & Design
| Fan | 120 mm Hydro Dynamic Bearing (HDB) |
|---|---|
| Fan Control | Smart and Silent Fan Control (S2FC) |
| Modular | Non-Modular (Fixed Cables) |
| Cables | Braided black cables |
| PCB Layout | OptiSink for improved heat dissipation |
Connectors & Protections
| Motherboard Connector | 20+4 pin ATX (55 cm) |
|---|---|
| PCIe Connectors | 1× 12V-2×6 (16-pin), 2× 8-pin PCIe |
| SATA Power Connectors | 2 |
| Peripheral (Molex) Connectors | 2 |
| Protections | OCP, OVP, UVP, OPP, SCP, OTP |
| Certifications | 80 PLUS Gold, BSMI, C-tick, CB, CCC, CE, cTUVus, EAC, FCC, TUV, UKCA, ErP Lot 6, Energy Star, REACH, RoHS, WEEE |
Shipping
All our products are shipped from the United Kingdom within 24 to 48 hours of purchase. See our Shipping and Returns page for full details.
Returns
- Tech Syndicate offers a full money-back guarantee on all purchases made in our store. If you are not satisfied with your purchase, we will provide a full refund, no questions asked.
- Refunds are available within 45 days of delivery.
- After the 45-day period you are no longer eligible for a refund, so we encourage you to try the product within the first few weeks to make sure it fits your needs.