The Seasonic X-Series was pioneering in obtaining the industry’s first 80 PLUS® Gold certification in 2009. Its 80 PLUS® Gold efficiency rating guarantees that efficiency will stay above 87 % at all loading levels. Moreover, the X-Series is also compliant with the Energy Star 5.0 rating and reduces energy consumption under standby, sleep and idle mode. This Seasonic market leader series it is a true representative of Green PC technology, which has many built-in features to help computer users lower their electricity bills. These power supplies are real top performers in Seasonic’s fully modular, multi-output ATX power supply family. All X-Series units also feature a patented design of DC Connector Module with Integrated VRM, with which these units achieve near-perfect DC-to-DC conversion, along with a true power factor above 0.9.

  • ATX 12 V
  • Fully modular
  • 80 PLUS Gold Certified
  • 7 Years Warranty
  • Dimensions: 150 mm (W) x 190 mm (L) x 86 mm (H)
  • Dimensions: 150 mm (W) x 160 mm (L) x 86 mm (H)


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80 PLUS®Gold

Seasonic was the forerunner of creating the very first 80 PLUS® Gold certified power supply on the market and since that time it has built a very popular Gold series lineup that covers a full power range of power supplies with impeccable performance and efficiency.

The highly efficient 80 PLUS® Gold certification guarantees greater than 87 %, 90 % and 87 % efficiency at 20 %, 50 % and 100 % operating loads, respectively. The clear advantage of buying a power supply with 80 PLUS® Gold rating is the fact that the less energy gets wasted during power conversion, the lower the operating costs will be for the user.

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).

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.

Dual Copper Bars

Due to their increased diameter, pure copper bars carry high current much more effectively than the traditional copper strips. If the goal is to achieve high quality power conversion with stable power output and minimized loss, it is very important that power conduction in the high wattage area remains extremely efficient, because it also reduces impedance and minimizes voltage drop as the load increases. (The feature only applies to X-1250 and X-1050)

105 °C Japanese Capacitor

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

Stable Voltage Regulation (2 %)

Improved voltage regulation stays well within Intel’s specifications to ensure smooth operation and protect all system components.

feature summary

  • 80 PLUS® Gold certified
  • Stable Voltage Regulation (2 %)
  • DC to DC Converter Design
  • S3FC - Fanless until 30 % load
  • Multi-GPU setup
  • Gold plated connectors
  • 7 years warranty



Technical Specifications
80PLUS® Gold
Form Factor Intel ATX 12 V
Dimensions 150 mm (W) x 160 mm (L) x 86 mm (H)
Fan Information Fan Size 120 mm
Fan Control Seasonic S3FC
Fan Bearing Double Ball Bearing
Life Expectancy 70,000 at 40 °C, 15 % - 65 % R.H.
Cable Information Modularity Fully Modular
Cable type Flat black cables
Electrical Features Operating Temperature 0 - 50 °C (derating from 100 % to 80 % from 40 °C to 50 °C)
MTBF @ 25 °C, excl. fan 150,000 hours
AC Input Full Range
Protection OPP, OVP, UVP, OCP, OTP, SCP
Safety and Environmental Safety and EMC cTUVus, TUV, Gost-R, CB , BSMI, CCC, CE, FCC, RCM
Environmental Compliance Energy Star, RoHS, WEEE, ErP Lot 6, REACH
Warranty 7 Years
Power Output
AC Input Voltage: 100 V - 240 V
Current: 15-7.5 A
Frequency: 50 Hz - 60 Hz
DC Output Rail +3.3 V +5 V +12 V -12 V +5 VSB
Maximum Power 25 A 25 A 104 A 0.5 A 3 A
125 W 1248 W 6 W 15 W
Total continuous power 1250 W



ConnectorConnector CountCable Length
Main Power (24/20 pins) 1 1 x 610 mm - modular
CPU (8/4 pins) 2 1 x 650 mm - 8/4pins modular
1 x 650 mm - 8 pins modular
PCIe (8/6 pins) 10 5 x 550 + 100 mm - modular
SATA 14 3 x 400 + 120 + 120 + 120 mm - modular
1 x 300 + 120 mm - modular
Peripheral 5 1 x 400 + 120 + 120 mm - modular
1 x 300 + 120 mm - modular
Floppy 1 1 x 101 mm - modular

Specifications are subject to change without prior notice.