FlexGURU 300W (New Edition)

  • Compliant with the latest Flex ATX V1.22
  • 300W : Efficiency ≥ 90% at typical load
  • 250W : Efficiency ≥ 85% at typical load
  • Compliant with the latest UL/EN/IEC 62368
  • Intelligent fan speed control
  • Quiet and long-lasting 40mm ball bearing fan
  • Includes power cable
  • Includes 20+4 pin, 4+4 pin, Molex and SATA cables
  • Ribbon cable design for DIY enthusiasts
  • Powerful single +12V rail design
  • Main Japanese electrolytic capacitors
  • Intel latest CPU ready
  • Complete protections: UVP, OVP, SCP, OPP, OTP
  • 80plus_Gold
  • 62368

Fully Modular Design

A fully modular design with all black ribbon cables simplifies installation, which allows you to use only the cables you need for a cleaner build.

High Power Density

The FlexGURU series features higher power density, 20% higher than any Flex PSU in the same wattage category.

Firm Installation with Beetle Technology

FSP pioneered the development of the Beetle technology in its Flex ATX PSU. The new Beetle technology strengthens the fixation adequacy by 25%, which allows the PSU to fit into most Flex ATX chassis available on the market today.

Excellent Thermal Performance

The FlexGURU series differs from the general Flex PSU by offering a built-in inner 40mm fan. This reduces noise and offers maximum cooling at all times.

90% Efficiency Conversion

The efficiency of your power supply directly affects your system's performance. The FlexGURU 300W has a guaranteed typical efficiency of 90%, which offers high conversion power to boost your system.

Application Field

Industrial PC

  • Industrial PC

  • Point of Sale System

  • Network communication

  • Surveillance

  • Edge Computer

  • Home Theater Personal Computer

  • NAS Server

  • Gaming & Creator PC

Keep in Compliance UL 62368

FSP Group brings you the latest technologies in renewable energy. FSP provides a full range of additional safety features to keep up with the latest regulations. FSP has upgraded the majority of their power supplies to the latest UL 62368 standard.

Safety Protection

OVP (Over Voltage Protection), UVP (Under Voltage Protection), OPP (Over Power Protection), SCP (Short Circuit Protection), and OTP (Over Temperature Protection), a full guardian circuit protections to keep your hardware safe.

100% Japanese Electrolytic Capacitors

Using Japanese electrolytic capacitors, the FlexGURU series offers stable output and the long-term reliability that you need.




AC Input100-240Vac~  6-3A  50-60Hz
DC Output+3.3V+5V+12V-12V+5Vsb
Max Output Current12A14A25A0.3A3A
Max Combined Power70W 
Total Power300W


 atx cable 24 pinEPS 4 4 pinhd statmolex
ATX 20+44+4 PINSATAMolex
*Cable Set #111  
*Cable Set #2  21
*Cable Set #1  3 
*There are 3 sets of cables available for different cable combinations.
(ie. Cable #1 & #2 or Cable #1 & #3)


Model FSP300-57FCB
Rated Output Power 300W
Form Factor Flex ATX
Input Voltage 100-240V
Input Current 6-3A
Input Frequency 50-60Hz
PFC Active PFC
Efficiency ≥90% at typical load
Fan Type Ball Bearing, 40mm
Dimensions(L x W x H) 150 x 40.5 x 81.5mm
Protection UVP, OVP, SCP, OPP, OTP