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BitFenix Formula Gold 450W PSU Review: Compact, Efficient, And Near-Silent

Load Regulation, Hold-Up Time & Inrush Current

To learn more about our PSU tests and methodology, please check out How We Test Power Supply Units. 

Primary Rails And 5VSB Load Regulation

Load Regulation testing is detailed here.

Hold-Up Time

Our hold-up time tests are described in detail here.

Measured hold-up time was over 17ms, while the power-good signal's hold-up time came close to 16ms. Most important, it was accurate.

Inrush Current

For details on our inrush current testing, please click here.

The inrush current was low with 115V and a bit high with 230V input.

Load Regulation And Efficiency Measurements

The first set of tests reveals the stability of the voltage rails and the BF450G’s efficiency. The applied load equals (approximately) 10 to 110 percent of the PSU's maximum load in increments of 10 percentage points.

We conducted two additional tests. During the first, we stressed the two minor rails (5V and 3.3V) with a high load, while the load at +12V was only 0.1A. This test reveals whether a PSU is compatible with Intel's C6/C7 sleep states or not. In the second test, we determined the maximum load the +12V rail could handle with minimal load on the minor rails.

Test #12V5V3.3V5VSBDC/AC (Watts)EfficiencyFan SpeedPSU NoiseTemps (In/Out)PF/AC Volts
11.944A1.983A1.981A0.985A44.89382.577%537 RPM10.3 dB(A)38.21°C0.936
24.885A2.976A2.971A1.184A89.39387.655%537 RPM10.3 dB(A)38.67°C0.972
38.229A3.473A3.454A1.384A134.49789.423%537 RPM10.3 dB(A)38.93°C0.982
411.576A3.970A3.964A1.585A179.69889.925%537 RPM10.3 dB(A)39.55°C0.986
514.595A4.963A4.955A1.787A225.02990.080%537 RPM10.3 dB(A)40.18°C0.989
617.546A5.957A5.946A1.990A269.52489.756%537 RPM10.3 dB(A)40.50°C0.990
720.566A6.952A6.937A2.194A314.83688.872%678 RPM15.3 dB(A)41.83°C0.990
823.591A7.947A7.932A2.399A360.14888.233%854 RPM21.2 dB(A)42.67°C0.990
927.018A8.446A8.414A2.401A405.03587.870%1182 RPM31.1 dB(A)43.34°C0.990
1030.384A8.945A8.930A2.505A449.76887.287%1346 RPM34.3 dB(A)45.21°C0.990
1134.153A8.948A8.931A2.507A494.57986.736%1630 RPM39.4 dB(A)46.29°C0.991
CL10.738A12.001A12.000A0.000A109.28484.933%545 RPM10.9 dB(A)43.59°C0.978
CL237.514A1.001A1.000A1.000A461.36588.330%1346 RPM34.3 dB(A)45.13°C0.991

Load regulation on all of the rails was tight, and we like that this PSU features quiet operation even under the taxing conditions of our test bench. It took cranking the load up to 110% of the BF450G's maximum-rated capacity and dialing the temperature beyond 46°C to make this PSU's fan spin at full speed. Even then, noise output remained under 40 dB(A). Although we ran our tests at grueling ambient temperatures, BitFenix's BF450G showed that it deserves its 80 PLUS Gold certification.

As we noted with the BF650G, our power factor readings were a little on the low side. CWT should tune its APFC converter for better performance.

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Aris Mpitziopoulos
Aris Mpitziopoulos

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.

  • 2Be_or_Not2Be
    Nice - I really like how quiet these models are running.

    Of course, it's also funny that the Formula Gold model is less noisy on average than its "Whisper" mate.
  • Dark Lord of Tech
    Excellent , thanks Aris!