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Primary Rails And 5VSB Load Regulation
The following charts show the main rails' voltage values recorded between a range of 40W up to the PSU's maximum specified load, along with the deviation (in percent). Tight regulation is an important consideration every time we review a power supply because it facilitates constant voltage levels despite varying loads. Tight load regulation also, among other factors, improves the system’s stability, especially under overclocked conditions and, at the same time, it applies less stress to the DC-DC converters that many system components utilize.
Load regulation is tight at 12V and 5V, satisfactory at 3.3V, and loose at 5VSB.
Hold-Up Time
Put simply; hold-up time is the amount of time that the system can continue to run without shutting down or rebooting during a power interruption.
The hold-up time is long and the power ok signal is accurate.
Inrush Current
Inrush current, or switch-on surge, refers to the maximum, instantaneous input current drawn by an electrical device when it is first turned on. A large enough inrush current can cause circuit breakers and fuses to trip. It can also damage switches, relays, and bridge rectifiers. As a result, the lower the inrush current of a PSU right as it is turned on, the better.
Despite the lack of an NTC thermistor, the inrush current is low.
Leakage Current
In layman's terms, leakage current is the unwanted transfer of energy from one circuit to another. In power supplies, it is the current flowing from the primary side to the ground or the chassis, which in the majority of cases is connected to the ground. For measuring leakage current, we use a GW Instek GPT-9904 electrical safety tester instrument.
The leakage current test is conducted at 110% of the DUT's rated voltage input (so for a 230-240V device, we should conduct the test with 253-264V input). The maximum acceptable limit of a leakage current is 3.5 mA and it is defined by the IEC-60950-1 regulation, ensuring that the current is low and will not harm any person coming in contact with the power supply's chassis.
Leakage Current Comments
10-110% Load Tests
These tests reveal the PSU's load regulation and efficiency levels under high ambient temperatures. They also show how the fan speed profile behaves under increased operating temperatures.
| Test # | 12V | 5V | 3.3V | 5VSB | DC/AC (Watts) | Efficiency | Fan Speed (RPM) | PSU Noise (dB[A]) | Temps (In/Out) | PF/AC Volts |
| 1 | 5.269A | 1.984A | 1.966A | 0.991A | 84.963 | 86.569% | 0 | <6.0 | 43.85°C | 0.970 |
| 12.026V | 5.040V | 3.354V | 5.049V | 98.145 | 40.41°C | 115.11V | ||||
| 2 | 11.578A | 2.979A | 2.955A | 1.193A | 170.042 | 90.463% | 603 | 13.4 | 40.48°C | 0.987 |
| 12.018V | 5.035V | 3.350V | 5.029V | 187.969 | 44.30°C | 115.11V | ||||
| 3 | 18.224A | 3.480A | 3.453A | 1.397A | 255.057 | 91.733% | 606 | 13.6 | 41.16°C | 0.997 |
| 12.017V | 5.030V | 3.346V | 5.011V | 278.044 | 45.62°C | 115.10V | ||||
| 4 | 24.884A | 3.979A | 3.948A | 1.603A | 340.088 | 91.556% | 608 | 13.6 | 41.99°C | 0.996 |
| 12.011V | 5.028V | 3.343V | 4.992V | 371.454 | 47.24°C | 115.10V | ||||
| 5 | 31.202A | 4.977A | 4.942A | 1.811A | 425.027 | 91.040% | 610 | 13.8 | 42.31°C | 0.997 |
| 12.003V | 5.024V | 3.339V | 4.972V | 466.858 | 48.16°C | 115.10V | ||||
| 6 | 37.489A | 5.977A | 5.939A | 2.000A | 509.470 | 90.375% | 877 | 25.0 | 42.75°C | 0.998 |
| 11.997V | 5.020V | 3.335V | 4.952V | 563.727 | 49.30°C | 115.09V | ||||
| 7 | 43.856A | 6.980A | 6.935A | 2.232A | 594.915 | 89.598% | 1079 | 32.1 | 43.56°C | 0.998 |
| 11.989V | 5.016V | 3.332V | 4.931V | 663.979 | 50.82°C | 115.09V | ||||
| 8 | 50.231A | 7.985A | 7.934A | 2.445A | 680.248 | 88.764% | 1201 | 35.4 | 43.96°C | 0.998 |
| 11.981V | 5.012V | 3.328V | 4.910V | 766.357 | 52.05°C | 115.09V | ||||
| 9 | 57.006A | 8.488A | 8.424A | 2.451A | 765.179 | 87.934% | 1496 | 41.0 | 44.84°C | 0.998 |
| 11.975V | 5.009V | 3.325V | 4.898V | 870.170 | 53.71°C | 115.08V | ||||
| 10 | 63.530A | 8.995A | 8.944A | 3.088A | 849.991 | 86.925% | 1498 | 40.9 | 45.17°C | 0.999 |
| 11.967V | 5.005V | 3.321V | 4.859V | 977.840 | 54.72°C | 115.07V | ||||
| 11 | 70.651A | 8.997A | 8.951A | 3.095A | 934.772 | 85.807% | 1498 | 40.9 | 46.69°C | 0.999 |
| 11.961V | 5.003V | 3.318V | 4.848V | 1089.392 | 57.44°C | 115.06V | ||||
| CL1 | 0.122A | 14.004A | 14.000A | 0.000A | 118.596 | 81.726% | 617 | 14.5 | 41.88°C | 0.980 |
| 12.018V | 5.022V | 3.343V | 5.064V | 145.114 | 48.25°C | 115.13V | ||||
| CL2 | 70.843A | 0.999A | 1.000A | 1.000A | 861.651 | 87.494% | 1496 | 41.0 | 45.60°C | 0.999 |
| 11.975V | 5.021V | 3.331V | 4.959V | 984.809 | 55.04°C | 115.07V |
The PSU doesn't have a problem delivering full power, or even more, under high operating temperatures. Moreover, it delivers high PF readings even under low loads.
20-80W Load Tests
In the following tests, we measure the PSU's efficiency at loads significantly lower than 10% of its maximum capacity (the lowest load the 80 PLUS standard measures). This is important for representing when a PC is idle with power-saving features turned on.
| Test # | 12V | 5V | 3.3V | 5VSB | DC/AC (Watts) | Efficiency | Fan Speed (RPM) | PSU Noise (dB[A]) | PF/AC Volts |
| 1 | 1.240A | 0.500A | 0.501A | 0.200A | 20.150 | 58.903% | 0 | <6.0 | 0.892 |
| 12.039V | 5.044V | 3.358V | 5.090V | 34.209 | 115.12V | ||||
| 2 | 2.467A | 0.991A | 0.984A | 0.394A | 39.981 | 80.087% | 0 | <6.0 | 0.931 |
| 12.031V | 5.042V | 3.357V | 5.079V | 49.922 | 115.11V | ||||
| 3 | 3.705A | 1.488A | 1.473A | 0.592A | 60.011 | 84.523% | 0 | <6.0 | 0.959 |
| 12.029V | 5.041V | 3.355V | 5.068V | 71.000 | 115.11V | ||||
| 4 | 4.936A | 1.984A | 1.969A | 0.791A | 79.962 | 86.302% | 0 | <6.0 | 0.966 |
| 12.026V | 5.039V | 3.354V | 5.057V | 92.654 | 115.11V |
Efficiency with 20W load is low, very low. With higher loads, efficiency exceeds the 80% mark.
2% or 10W Load Test
Intel plans on raising the ante at efficiency levels under ultra-light loads. So from July 2020, the ATX spec will require 70% and higher efficiency with 115V input. The applied load is only 10W for PSUs with 500W and lower capacities, while for stronger units we dial 2% of their max-rated-capacity.
| Test # | 12V | 5V | 3.3V | 5VSB | DC/AC (Watts) | Efficiency | Fan Speed (RPM) | PSU Noise (dB[A]) | PF/AC Volts |
| 1 | 1.224A | 0.250A | 0.251A | 0.052A | 17.103 | 56.515% | 0 | <6.0 | 0.870 |
| 12.037V | 5.043V | 3.358V | 5.096V | 30.263 | 115.12V |
As expected, the PSU doesn't deliver high efficiency with super-light loads.
Efficiency & Power Factor
Next, we plotted a chart showing the PSU’s efficiency at low loads, and loads from 10 to 110% of its maximum rated capacity. The higher a PSU’s efficiency, the less energy goes wasted, leading to a reduced carbon footprint and lower electricity bills. The same goes for Power Factor.
Efficiency is high with normal loads but bottom low at light and super-light loads. On the other hand, PF readings are high with both 115V and 230V input.
5VSB Efficiency
| Test # | 5VSB | DC/AC (Watts) | Efficiency | PF/AC Volts |
| 1 | 0.100A | 0.510 | 74.561% | 0.092 |
| 5.095V | 0.684 | 115.11V | ||
| 2 | 0.250A | 1.273 | 77.527% | 0.168 |
| 5.089V | 1.642 | 115.11V | ||
| 3 | 0.550A | 2.793 | 78.588% | 0.256 |
| 5.077V | 3.554 | 115.11V | ||
| 4 | 1.000A | 5.060 | 78.927% | 0.307 |
| 5.060V | 6.411 | 115.11V | ||
| 5 | 1.500A | 7.561 | 78.834% | 0.337 |
| 5.040V | 9.591 | 115.12V | ||
| 6 | 3.000A | 14.941 | 77.435% | 0.376 |
| 4.980V | 19.295 | 115.12V |
The 5VSB rail is efficient.
Power Consumption In Idle And Standby
| Mode | 12V | 5V | 3.3V | 5VSB | Watts | PF/AC Volts |
| Idle | 12.039V | 5.042V | 3.357V | 5.100V | 4.606 | 0.388 |
| 115.1V | ||||||
| Standby | 0.070 | 0.009 | ||||
| 115.1V |
Vampire power could be lower, with 230V input.
Fan RPM, Delta Temperature, And Output Noise
All results are obtained between an ambient temperature of 37 to 47 degrees Celsius (98.6 to 116.6 degrees Fahrenheit).
The fan speed profile could have more steps, especially at lower loads. This would offer a more linear fan speed increase.
The following results were obtained at 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit) ambient temperature.
The PSU's passive operation doesn't last long, but at least the output noise remains low at up to 450W load. With higher than 650W loads, the fan's noise exceeds 35 dBA, and after 720W, you will be treated with over 40 dBA. This means that the fan speed profile could be more relaxed under normal operating temperatures.
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