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Seasonic
Seasonic Focus GX-850 (ATX 3.1)
850 W · fully modular
- Wattage 850 W · fully modular
- Standard ATX 3.1, PCIe 5.1
- GPU connector 12V-2x6
- Efficiency 80 PLUS Gold
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Price, availability and customer reviews are on Amazon.
Amazon listing: “Seasonic Focus GX-850 850W Power Supply ATX 3.1 & PCIe 5.1 Ready” · ASIN B0DLFMTX12
Who it’s for
An alternative to the RM850x with the same standard and warranty length.
Pros
- ATX 3.1 with a 12V-2x6 cable
- 10-year warranty
Cons
- Same 850 W ceiling: not for an RTX 5090
Pros and cons come from the maker’s specs below, not from testing this unit. How we pick.
Specifications
| Wattage | 850 W · fully modular |
|---|---|
| Standard | ATX 3.1, PCIe 5.1 |
| GPU connector | 12V-2x6 |
| Efficiency | 80 PLUS Gold |
| Warranty | 10 years |
Source: Best Buy spec sheet · Amazon listing checked 2026-09-29.
Compare with other power & protection
| Product | Wattage | Standard | GPU connector | Efficiency | Warranty |
|---|---|---|---|---|---|
| Corsair RM850x (ATX 3.1) | 850 W · fully modular | ATX 3.1, PCIe 5.1 | Native 12V-2x6 | Cybenetics Gold | 10 years |
| Seasonic Focus GX-850 (ATX 3.1)This product | 850 W · fully modular | ATX 3.1, PCIe 5.1 | 12V-2x6 | 80 PLUS Gold | 10 years |
| Corsair RM1000x (ATX 3.1) | 1000 W · fully modular | ATX 3.1, PCIe 5.1 | 12V-2x6 | — | — |