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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.

Bitfenix BF450G

EVGA 450 BT

EVGA 450 B3

Primary Rails And 5VSB Load Regulation

Load Regulation testing is detailed here.

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Hold-Up Time

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

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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.

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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.

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Test #	12V	5V	3.3V	5VSB	DC/AC (Watts)	Efficiency	Fan Speed	PSU Noise	Temps (In/Out)	PF/AC Volts
1	1.944A	1.983A	1.981A	0.985A	44.893	82.577%	537 RPM	10.3 dB(A)	38.21°C	0.936
11.978V	5.043V	3.334V	5.079V	54.365	44.74°C	115.32V
2	4.885A	2.976A	2.971A	1.184A	89.393	87.655%	537 RPM	10.3 dB(A)	38.67°C	0.972
11.973V	5.041V	3.333V	5.068V	101.983	45.89°C	115.26V
3	8.229A	3.473A	3.454A	1.384A	134.497	89.423%	537 RPM	10.3 dB(A)	38.93°C	0.982
11.968V	5.040V	3.332V	5.058V	150.406	47.48°C	115.20V
4	11.576A	3.970A	3.964A	1.585A	179.698	89.925%	537 RPM	10.3 dB(A)	39.55°C	0.986
11.963V	5.040V	3.331V	5.048V	199.831	49.23°C	115.13V
5	14.595A	4.963A	4.955A	1.787A	225.029	90.080%	537 RPM	10.3 dB(A)	40.18°C	0.989
11.957V	5.039V	3.331V	5.038V	249.811	51.38°C	115.16V
6	17.546A	5.957A	5.946A	1.990A	269.524	89.756%	537 RPM	10.3 dB(A)	40.50°C	0.990
11.952V	5.038V	3.330V	5.027V	300.284	54.09°C	115.09V
7	20.566A	6.952A	6.937A	2.194A	314.836	88.872%	678 RPM	15.3 dB(A)	41.83°C	0.990
11.948V	5.036V	3.330V	5.015V	354.258	56.42°C	115.02V
8	23.591A	7.947A	7.932A	2.399A	360.148	88.233%	854 RPM	21.2 dB(A)	42.67°C	0.990
11.942V	5.035V	3.329V	5.004V	408.177	57.83°C	114.95V
9	27.018A	8.446A	8.414A	2.401A	405.035	87.870%	1182 RPM	31.1 dB(A)	43.34°C	0.990
11.937V	5.034V	3.328V	4.999V	460.950	58.67°C	114.99V
10	30.384A	8.945A	8.930A	2.505A	449.768	87.287%	1346 RPM	34.3 dB(A)	45.21°C	0.990
11.932V	5.032V	3.327V	4.992V	515.274	60.92°C	114.92V
11	34.153A	8.948A	8.931A	2.507A	494.579	86.736%	1630 RPM	39.4 dB(A)	46.29°C	0.991
11.927V	5.032V	3.326V	4.988V	570.212	62.27°C	114.85V
CL1	0.738A	12.001A	12.000A	0.000A	109.284	84.933%	545 RPM	10.9 dB(A)	43.59°C	0.978
11.960V	5.035V	3.336V	5.082V	128.671	55.49°C	115.22V
CL2	37.514A	1.001A	1.000A	1.000A	461.365	88.330%	1346 RPM	34.3 dB(A)	45.13°C	0.991
11.941V	5.037V	3.328V	5.041V	522.320	58.13°C	114.92V

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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