Seasonic
Seasonic CORE GX-850 850W Power Supply ATX 3.1 & PCIe 5.1 Ready
Bottom line: The Seasonic CORE GX-850 850W Power Supply ATX 3.1 & PCIe 5.1 Ready: Native 12V-2x6 connector for RTX 5080 and other ATX 3.1 / PCIe 5.1 GPUs; main trade-off: 850W leaves little headroom for RTX 5090-class cards or heavy overclocking.
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Pros & Cons
Pros
- ✓ Native 12V-2x6 connector for RTX 5080 and other ATX 3.1 / PCIe 5.1 GPUs
- ✓ 80 Plus Gold and Cybenetics Platinum certified efficiency
- ✓ Fully modular cabling, so you only run the cables your build needs
- ✓ Includes a 12V-2x6 to dual 8-pin PCIe cable for older or AMD RX 9000 cards
- ✓ 7-year warranty backs the 850W unit
Cons
- ✗ 850W leaves little headroom for RTX 5090-class cards or heavy overclocking
- ✗ Listing omits fan size and dimensions, so check case fit before you buy
- ✗ Gold rated under 80 Plus, below Platinum or Titanium units at full load
- ✗ Listing does not state SATA, Molex or EPS cable counts
SpecPicks Verdict
SpecPicks scored Seasonic CORE GX-850 850W Power Supply ATX 3.1 & PCIe 5.1 Ready using a rating × review-volume × price-fit model applied to published specs and reviews across the power supplies category. Seasonic's power supplies lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
Common buyer scenarios for power supplies of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Key Features
- ATX 3.1 / PCIE 5.1 ready. Native 12V-2x6 connector
- 80 PLUS Gold and Cybenetics Platinum certified
- OptiSink Design
- NVIDIA RTX 5080 AMD RX 9000 ready
- 12V-2x6 to dual 8-pin PCIe cable included
Full Specifications
| Brand | Seasonic |
|---|---|
| Wattage | 850 watts |
| Model Name | Core GX-850 ATX 3.1 |
| Unit Count | 1 Count |
| Form Factor | ATX |
| Model Number | Core GX-850 ATX 3.1 |
| Connector Type | ATX |
| Cooling Method | Air |
| Number of Fans | 1 |
| Output Wattage | 850 |
| Item Dimensions | 5.5 x 5.9 x 3.4 inches |
| Mfr Part Number | Core GX-850 ATX 3.1 |
| Number of Items | 1 |
| Number of Packs | 1 |
| Compatible Devices | ATX motherboards, PCIe 5.0 graphics cards, standard ATX power supplies, various storage drives, and expansion cards |
| Warranty Description | 7 years |
| Maximum Input Voltage | 132 volts_of_alternating_current |
| Minimum Input Voltage | 120 volts_of_alternating_current |
| Item dimensions L x W x H | 5.5 x 5.9 x 3.4 inches |
| System Bus Connector Type | ATX |
| Full listing title | Seasonic CORE GX-850 850W Power Supply ATX 3.1 & PCIe 5.1 Ready | 80 Plus Gold & Cybenetics Platinum Fully Modular 12V-2x6 RTX 5080 AMD RX 9000 Ready OptiSink Design 7 Years Warranty |
Ready to buy?
Seasonic CORE GX-850 850W Power Supply ATX 3.1 & PCIe 5.1 Ready | 80 Plus Gold & Cybenetics Platinum Fully Modular 12V-2x6 RTX 5080 AMD RX 9000 Ready OptiSink Design 7 Years Warranty is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
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