Final Thoughts and Conclusions
With the introduction of the FOCUS SGX series, Seasonic now has two SFX-L power supplies to offer small form-factor enthusiasts. And as we have come to expect from Seasonic, the overall performance was very good to excellent.
The voltage regulation for the three main outputs (+12V, +5V, and +3.3V) was excellent and easily exceeded Seasonic’s own claim of ±3%. The all important +12V output stayed within 1%. AC ripple and noise suppression was also very good staying well below the recommended guidelines. And the power supply features a good assortment of modular cables and delivers good efficiency, easily meeting the 80Plus Gold criteria.
In the past many SFX power supplies were very noisy due to a high-speed 80mm fan. But with a slightly lengthened chassis and a 120mm fan onboard the SGX-650 was silent to relatively quiet from low through mid-power outputs thanks to Seasonic’s Hybrid Silent Fan Control that allows silent, fanless operation below about 30% load.
We were a bit surprised to see the 650W max output power de-rated to 520W (80% laod) when the operating temperature exceeds 40°C. And even though a SFX to ATX adapter bracket is included, the modular cables are intentionally short for small form-factor builds and will likely be too short to use in a larger case.
The MSRP for the two Seasonic SGX Series power supplies is currently:
• Seasonic FOCUS SGX-450 ($99.99 USD)
• Seasonic FOCUS SGX-650 ($129.99 USD)
Strengths:
• 650W of Continuous DC output at up to 40°C
• Easily meets 80 PLUS Gold certification criteria
• Excellent voltage regulation (±2%) on the three primary outputs
• Very good AC ripple and noise suppression
• Quiet 120mm cooling fan with a fluid dynamic bearing (FDB)
• Hybrid Silent Fan Control allows silent, fan-less operation at low power
• Compact SFX-L chassis measures 125mm square
• Good assortment of fully modular cables with (4) PCI-E connectors
• All Japanese made capacitors for reliable operation
• 10-Year warranty
Minor Weaknesses:
• Max output de-rated to 520W when operating above 40°C
• Cables may be too short when used in a larger case via the SFX to ATX adapter
Seasonic FOCUS SGX-650 SFX-L Power Supply
Our thanks to Seasonic for sending us the SGX-650 PSU to review.
Fun fact: If you are talking
Fun fact: If you are talking about the company, then it is Sea Sonic Electronics Co. Note that it is not “Seasonic” but two words “Sea Sonic”. But if you are talking about the brand, then it is just one word “Seasonic”.
But it gets even funnier than that. The naming of the American subsidiary of Sea Sonic is following the brand name: Seasonic Electronics Inc. But the European subsidiary then is following the name of the mother company again: Sea Sonic Europe B.V.
That said, i really like their PSUs despite the mind-bending name shenanigans. 😉