Seasonic
Seasonic S12III 650 SSR-650GB3 650W 80+ Bronze ATX12V & EPS12V Direct Cable Wire Output Smart & Silent Fan Control Power Supply
Status: Seasonic S12III 650 SSR-650GB3 650W 80+ Bronze…: Unavailable on Amazon as of . SpecPicks has no in-stock listing with matching specs on file; the search below lists current offers. eBay sellers may still list this model new or used.
Bottom line: The Seasonic S12III 650 SSR-650GB3 650W 80+ Bronze ATX12V & EPS12V Direct: 80 PLUS Bronze: 85% efficient at 50% load, 82% at 20% and 100%; main trade-off: fixed cabling - unused cables stay in the case, hurting airflow.
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Currently unavailable on Amazon. Not the same product — 3 in-stock alternatives:
Similar: Segotep 650W ATX Power Supply — $49.99 on Amazon as of 2026-10-06 12:20 UTC (price may vary).
Similar: Seasonic CORE GX-650 650W Power Supply ATX 3.1 &… — $114.98 on Amazon as of 2026-10-06 12:20 UTC (price may vary).
Similar: GOLDEN FIELD 650W Power Supply 80+ Gold Full… — $56.99 on Amazon as of 2026-10-06 22:21 UTC (price may vary).
Pros & Cons
Pros
- ✓ 80 PLUS Bronze: 85% efficient at 50% load, 82% at 20% and 100%
- ✓ S2FC fan control scales the 120 mm fan to actual system load
- ✓ Active PFC reduces wasted energy over the build's life
Cons
- ✗ Fixed cabling - unused cables stay in the case, hurting airflow
- ✗ Sleeve bearing fan is shorter-lived than fluid dynamic or ball designs
- ✗ Bronze tier trails Gold and Platinum units on efficiency
- ✗ 650W ceiling limits headroom for high-draw flagship GPU builds
Manufacturer description
The Seasonic S12III 650 (SSR-650GB3) is a 650W ATX12V and EPS12V power supply built for standard mid-tower PC builds that need dependable rails without a modular price premium. It carries 80 PLUS Bronze certification, delivering 82% efficiency at 20% load, 85% at 50% load, and 82% at 100% load, so less of what you pull from the wall is wasted as heat. Active Power Factor Correction works alongside that efficiency curve to trim energy waste over the life of the build. Cooling comes from a 120 mm sleeve bearing fan governed by Seasonic's S2FC fan control, which scales fan speed to the load…
SpecPicks Verdict
SpecPicks scored Seasonic S12III 650 SSR-650GB3 650W 80+ Bronze ATX12V & EPS12V… 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.
Frequently Asked Questions
Is the Seasonic S12III 650 modular?
No. It uses fixed cabling with direct cable wire output, supplying all the cables a standard PC build requires. Unused cables cannot be detached and must be routed or tucked inside the case.
How efficient is the S12III 650W?
It meets the 80 PLUS Bronze standard: 82% efficient at 20% load, 85% at 50% load, and 82% at 100% load. Active Power Factor Correction is also included to cut energy waste.
How long is the warranty on this Seasonic power supply?
Seasonic lists a 5 year warranty on the S12III Bronze series. Check the product listing for current warranty registration and regional terms before you buy.
Is the S12III 650 quiet under load?
The 120 mm sleeve bearing fan is regulated by Seasonic's S2FC fan control, which adjusts fan speed to what the system actually needs instead of running at a fixed RPM.
What form factor and standards does it support?
The S12III 650 is a standard ATX form factor unit supporting both ATX12V and EPS12V, so it fits typical mid-tower cases and supplies EPS connectors for motherboard CPU power.
Key Features
- Fixed cabling - Provides all the necessary cables required for a standard pc.
- 80 plus Bronze - 82% efficient at 20% load, 85% efficient at 50% load, and 82% efficient at 100% load.
- 120 mm SLEEVE BEARING FAN; The 120 mm fan inside is regulated by the Sea sonic S2FC fan control, which optimizes the fan speed according to the needs of the system to create a quiet and pleasant environment.
- 5 year warranty ; Our commitment to superior quality.
Full Specifications
| Brand | Seasonic |
|---|---|
| Wattage | 650 watts |
| Fan Size | 12 centimeters |
| Model Name | S12III 650 |
| Unit Count | 1 Count |
| Form Factor | ATX12V |
| Model Number | SSR-650GB3 |
| Compatibility | PC |
| Connector Type | ATX |
| Cooling Method | Air |
| Number of Fans | 1 |
| Output Wattage | 650 |
| Item Dimensions | 5.5 x 5.9 x 3.3 inches |
| Mfr Part Number | SSR-650GB3 |
| Number of Items | 1 |
| Compatible Devices | Personal Computer |
| Warranty Description | 5 years |
| Maximum Input Voltage | 240 volts_of_alternating_current |
| Minimum Input Voltage | 110 volts_of_alternating_current |
| Item dimensions L x W x H | 5.5 x 5.9 x 3.3 inches |
Ready to buy?
Seasonic S12III 650 SSR-650GB3 650W 80+ Bronze ATX12V & EPS12V Direct Cable Wire Output Smart & Silent Fan Control Power Supply 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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