Power Supply Seasonic GX-850 CORE GX ATX gold SRP-CGX851-A5A32SF 80 Plus Gold 850W

Seasonic GX-850 CORE V2 GX 850W ATX 3.1 80+ Gold Power Supply

Here Seasonic's CORE GX V2 line offers an 850-watt unit aimed at demanding system builders, with ATX 3.1 and PCIe 5.1 support and a comfortable value-to-performance balance. The unit is fully modular and carries an 80 PLUS Gold rating.

Power & efficiency

The supply delivers a continuous 850 watts on a +12V rail, which fits systems with a power-hungry CPU and graphics card. The 80 PLUS Gold standard keeps efficiency high across the load range, reducing energy wasted as heat. Full ATX 3.1 compliance lets it easily absorb the brief load spikes of current-generation components.

Cables & connectors

The fully modular design lets you connect only the cables you truly need, for clean cable management and better airflow. A native 12V-2x6 cable is engineered for PCIe 5.1 graphics cards and supports up to 600 watts, suiting NVIDIA RTX 40 and RTX 50 boards. For users on older cards, an adapter from 12V-2x6 to two PCIe 8-pin connectors is included, so you can upgrade the supply without swapping the GPU.

Reliability & cooling

Cooling relies on a 120 mm fan with a Hydro Dynamic Bearing that works together with Seasonic's Smart and Silent Fan Control to balance temperature and noise. At low loads the fan slows or stops to stay quiet, while at high loads it ramps up cooling to keep things stable over time.

• Brand: Seasonic
• Output: 850 W continuous
• Efficiency: 80 PLUS Gold
• Form factor: ATX, fully modular
• Standards: ATX 3.1 and PCIe 5.1
• GPU connector: native 12V-2x6 up to 600 W plus 2x PCIe 8-pin adapter
• Cooling: 120 mm HDB fan with Smart and Silent Fan Control