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be quiet!

be quiet! SFX Power 3 450W BN321 - 80 PLUS Bronze Non-Modular Compact PSU (Boxed)

SKU 6670 Brand be quiet! EAN13 4260052188279
Compact 450W SFX PSU with 80 PLUS Bronze efficiency, non-modular design, and ultra-quiet 80mm fan (33.8dB max). Ideal for mini-ITX and media center builds.
PSU (Power Supplies) - Wattage 400 - 499 W
PSU (Power Supplies) - Efficiency Rating 80 Plus Bronze
PSU (Power Supplies) - Color Black
PSU (Power Supplies) - Modularity Non-modular
PSU (Power Supplies) - PCIe GPU Connectors 2x 8/6 pins
PSU (Power Supplies) - Length Up to 140 mm
PSU (Power Supplies) - EPS CPU Connectors 1x 4+4pin EPS/ATX12V

The be quiet! SFX Power 3 450W (BN321) is a compact power supply engineered for mini-ITX and small form factor PC systems. Delivering 450W of continuous power with a 500W peak capacity, this PSU provides reliable performance for systems with powerful PCIe graphics cards while maintaining exceptional quietness. The high-quality 80mm temperature-controlled fan operates at a maximum of 33.8dB(A), ensuring silent operation even under full load.

With 80 PLUS Bronze certification and up to 89.3% efficiency, the SFX Power 3 minimizes power waste and reduces electricity costs. The non-modular cable design simplifies installation in compact cases, while the SFX12V 3.42 form factor (125mm × 100mm × 64mm) fits seamlessly into space-constrained builds. Featuring comprehensive protection against overcurrent, overvoltage, short circuits, and other electrical faults, this PSU is built for reliability and longevity with a 100,000-hour MTBF rating.

Key features include:

  • 450W continuous / 500W peak power output
  • 80 PLUS Bronze efficiency certification
  • Ultra-quiet 80mm rifle-bearing fan (max 33.8dB)
  • Non-modular fixed cables for compact installations
  • 2x PCIe 6+2 pin connectors for graphics cards
  • 1x 4+4 pin EPS connector for CPU power
  • 3x SATA and 2x Molex connectors
  • Active PFC and comprehensive protection features
  • RoHS and WEEE compliant
Continuous Power Output450 W
Peak Power Output500 W
Form FactorSFX12V 3.42
EPS Version2.92
Efficiency Rating80 PLUS Bronze (85.9% typical, up to 89.3%)
AC Input Voltage100 - 240 V
AC Input Frequency50 - 60 Hz
Input Current6 A @ 110V / 2.5 A @ 220V
Power Factor>0.98 at 100% load
Power Factor Correction TypeActive
+3.3V Rail Output85 W max, 16 A max
+5V Rail Output85 W max, 16 A max
+12V Rail Output450 W max, 37.5 A max
-12V Rail Output0.3 A max
+5V Standby Output2.5 A max
Hold-up Time21 ms
Standby Power Consumption<0.11 W
Protection FeaturesOvercurrent, Overvoltage, Undervoltage, Short Circuit, Overpower
Motherboard Connector20+4 pin ATX
Motherboard Cable Length35 cm
EPS CPU Connector1x 4+4 pin
PCIe GPU Connectors2x 6+2 pin
PCIe Cable Length55 cm
SATA Connectors3x
SATA Cable Lengths300 mm, 450 mm, 600 mm
Molex (4-pin) Connectors2x
Molex Cable Lengths300 mm, 450 mm
Floppy Connector1x
Floppy Cable Length60 cm
Cabling TypeNon-Modular
Fan Size80 mm
Fan TypeHigh-quality temperature-controlled
Bearing TechnologyRifle
Motor Technology4-pole fan motor
Maximum Fan Speed2366 RPM
Noise Level @ 10% Load13.2 dB(A)
Noise Level @ 20% Load13.2 dB(A)
Noise Level @ 50% Load13.2 dB(A)
Noise Level @ 100% Load33.8 dB(A)
TopologyDC/DC
Modern Standby SupportYes
MTBF100,000 hours
ColorBlack
Cooling TypeActive
On/Off SwitchYes
Unit Width125 mm
Unit Depth100 mm
Unit Height64 mm
Unit Weight890 g
Safety CertificationsCE, CB, TÜV, CU
Compliance StandardsRoHS, WEEE
Sustainability CertificationsENERGY STAR, ErP
HS Code84733020