This fully modular power supply is an ideal solution for average desktop systems where low energy usage and reduced noise levels are the basic requirements. The highly reliable components built into this power supply assure that this unit is not only an energy saver but will also last a long time. In this manner users can save money by deferring their purchases by not having to buy a new unit for a longer period of time. Ease of installation, cost efficiency and reliability are the key features of this remarkable Seasonic product.

SKU: SS-650KM3 Active PFC Categories: ,
Fan Control S3FC-01

Hybrid Silent fan Control

The industry’s first, Seasonic patented, advanced three-phased thermal control achieves optimal between silence and cooling. This Hybrid Silent Fan Control functions in three operational stages: Fanless Mode, Silent Mode, and Cooling Mode.


Benefits of this design

  • Reduced noise without increase in temperature;
  • Extended fan life due to the reduced number of fan rotations;
  • Optimized heat dissipation at all times;
  • Unsurpassed silent performance in Fanless Mode.

Additionally, there is a switch at the back of the power supply which allows users to customize their cooling needs by selecting between the Seasonic S2FC (fan control without Fanless Mode) and the S3FC (fan control including Fanless Mode).

Fan Type Sanyo Denki-01

Sanyo Denki Fan

The world-renowned Sanyo Denki ball bearing fans are made of the highest quality components to ensure ultra-low noise performance. The fan’s perfect balance and even rotations are achieved via the use of spoon-shaped, high-density plastic fan blades that are finished off with smoothed leading edges. Sanyo Denki fans are known for their strict tolerance ball bearings and precision copper axels. Instead of the industry standard of two balancing points they use three points to strengthen the mount and further stabilize the blade.

Japanese Capacitor-01

105 °C Japanese Capacitor

Premium quality Japanese capacitors with 105 °C rating increase overall reliability and extend product life.

DC to DC Converter Design-01

DC to DC Converter Design

The step down DC to DC converter design allows the power supply to be able to serve system components with various voltage needs. Not only is it a flexible, clean voltage conversion solution but it also maximizes the 12 V DC rail output, delivers superior dynamic response and , ultimately, provides for greater system stability.

Tight Voltage Regulation-01

Tight Voltage Regulation (3 %)

Seasonic’s advanced design is to improve load regulation which reduces voltage variations to provide smooth and stable operations.

Specifications are subject to change without prior notice.
Note: Since the beginning of 2015, Seasonic has implemented changes in its retail box design and modular cables are now packed in a black cardboard box.

AC InputVoltage: 100 V - 240 V
Current: 8.5 - 4 A
Frequency: 50 Hz - 60 Hz
DC OutputRail+3.3 V+5 V+12 V-12 V+5 VSB
Maximum Power25 A25 A54 A0.5 A3 A
125 W648 W6 W15 W
Total continuous power650 W
X-650 Technical Specifications
Form FactorIntel ATX 12 V
Dimensions150 mm (W) x 160 mm (L) x 86 mm (H)
Fan InformationFan Size120 mm
Fan ControlSeasonic S3FC
Fan BearingDouble Ball Bearing
Life Expectancy70,000 at 40 °C, 15 % - 65 % R.H.
Cable InformationModularityFully Modular
Cable typeFlat black cables
Electrical FeaturesOperating Temperature40 °C
MTBF @ 25 °C, excl. fan150,000 hours
AC InputFull Range
ProtectionOPP, OVP, UVP, OCP, OTP, SCP
Safety and EnvironmentalSafety and EMCcTUVus, TUV, Gost-R, CB , BSMI, CCC, CE, FCC, C-tick
Environmental ComplianceEnergy Star, RoHS, WEEE, ErP Lot 6, REACH
Warranty7 Years
Packaging information
Units per carton4
Individual carton size330 (L) x 130 (W) x 195 (H) mm
Shipping carton size545 (L) x 215 (W) x 405 (H) mm

Specifications are subject to change without prior notice.

ConnectorConnector CountLengths
MAIN-POWER-24-20-PIN-A1610 mm - modular
PCIE-8-PIN-A24/8 Pin - 650 mm- modular
8 Pin - 650 mm- modular
PCIE-6-8-PIN-1-A4550 + 100 mm - modular
550 + 100 mm - modular
SATA-5-PIN-A10400 + 120 + 120 + 120 mm - modular
400 + 120 + 120 + 120 mm - modular
300 + 120 mm - modular
PERIPHERAL-4-PIN-A5400 + 120 + 120 mm - modular
300 + 120 mm - modular
FDD-4-PIN-1-A1101 mm - modular

Specifications are subject to change without prior notice.





PC Ekspert | Editor’s Choice

July 23, 2015

“Tehničkim karakteristikama, performansama, kvalitetom izrade, opremom i napose cijenom, ovo Saeasonicovo X-650 napajanje spada u sam vrh ponude.”

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Kitguru | Must Have

February 22, 2013

“Another quality, rock solid power supply from Seasonic.”

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JonnyGURU | Recommended (9.1)

February 4, 2013

“On the efficiency front, this unit literally pole vaulted over the requirements to hit Gold certification in both the cold and hot tests, gaining enough space to even hit Platinum in the cold tests.”

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Hardware Secrets | Golden Award

December 12, 2012

“The new X-Series KM3 650 W is another flawless power supply from Seasonic, targeted to users who demand only “the best.” Its efficiency surpassed the numbers promised by the 80 Plus Gold certification, noise and ripple levels were very low, and voltage regulation was outstanding, with the main positive voltages (+12 V, +5 V, and +3.3 V) within 1% of their nominal values. The ATX12V specification allows a 5% deviation, and we usually consider units with 3% voltage regulation as “flawless.””

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Clube do Hardware | Recommended

December 12, 2012

“A nova X-Series KM3 650 W é mais uma fonte de alimentação impecável da Seasonic, direcionada a usuários que exigem o melhor. Sua eficiência ultrapassou os números prometidos pela certificação 80 Plus Gold, os níveis de oscilação e ruído foram bem baixos e a regulação de tensão foi excelente, com as principais tensões positivas (+12 V, +5 V e +3,3 V) ficando dentro de 1% de seus valores nominais. A especificação ATX12V permite uma tolerância de 5% e nós geralmente consideramos fontes com regulação de tensão de 3% como sendo impecáveis.”

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