FlexGURU 300W

  • Compliant with the latest Flex ATX V1.22
  • 300W : Efficiency ≥ 90% at typical load
  • 250W : Efficiency ≥ 85% at typical load
  • Compliant with UL/EN/IEC 62368-1 and 60950 International safety standards
  • Intelligent fan speed control
  • Quiet and long-lasting 40mm ball bearing fan
  • Ribbon cables for the need of 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

Fully modular design with all black ribbon cables simplifies installation, which allows you to use only the cables you need, for a much neater build.

High Power Density

Flexguru series featured with high power density, 20% higher than any Flex PSU in the same wattage and frame.

Firm Installation with Beetle Technology

FSP pioneered the development of the Beetle technology in FLEX-ATX PSU, and we applied it on the  FlexGuru series. The new technology strengthens the fixation adequacy by 25% which makes the PSU  fit in most of the Flex-ATX chassis in the market.

Excellent Thermal Performance

Differ from the genernal FLEX PSU, FlexGuru series is designed with inner 40mm fan, noise cancellation and achieving maximum cooling at all times.

90% Efficiency Conversion

The efficiency of your power supply directly affects your system’s performance. FlexGuru 300W has a guaranteed typical efficiency of 90%, offer the 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 IEC 62368

FSP Group brings you the latest technologies in renewable energy, they provide 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.

Japanese Electrolytic Capacitors

Using Japanese electrolytic capacitors, Flexguru series offers a stable output and long-term reliability 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 statmolex2.5 floppy
ATX 20+44+4 PINSATAMolex


Model FSP300-57FCB
Rated Output Power 300W
Form Factor FLEX ATX
Input Voltage 100-240V
Input Current 6-3A
Input Frequency 60-50Hz
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