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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.
The load regulation is super-tight at +12V and tight at 5V and 3.3V.
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 longer than 17ms, but the power-ok signal's hold-up time is a bit lower than 16ms, which is what the ATX spec requires. Nonetheless, this is due to the long delay.
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.
The inrush current readings are at normal levels, with both voltage inputs.
10-110% Load Tests
These tests reveal the PH-P650G'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 | 3.567A | 2.009A | 1.995A | 0.980A | 64.928 | 83.985% | 0 | <6.0 | 44.79°C | 0.961 |
| 12.147V | 4.978V | 3.307V | 5.103V | 77.309 | 40.15°C | 115.14V | ||||
| 2 | 8.111A | 3.016A | 2.995A | 1.179A | 129.417 | 88.789% | 0 | <6.0 | 45.77°C | 0.982 |
| 12.146V | 4.974V | 3.305V | 5.090V | 145.758 | 40.51°C | 115.14V | ||||
| 3 | 13.050A | 3.522A | 3.480A | 1.379A | 194.522 | 90.044% | 0 | <6.0 | 46.87°C | 0.987 |
| 12.147V | 4.971V | 3.303V | 5.077V | 216.029 | 40.86°C | 115.15V | ||||
| 4 | 17.990A | 4.027A | 3.997A | 1.580A | 259.746 | 90.199% | 0 | <6.0 | 47.73°C | 0.989 |
| 12.148V | 4.968V | 3.301V | 5.065V | 287.971 | 41.40°C | 115.14V | ||||
| 5 | 22.596A | 5.037A | 5.003A | 1.782A | 325.050 | 89.905% | 555 | 8.4 | 42.53°C | 0.990 |
| 12.150V | 4.965V | 3.298V | 5.051V | 361.547 | 49.37°C | 115.14V | ||||
| 6 | 27.143A | 6.047A | 6.008A | 1.986A | 389.571 | 89.336% | 567 | 8.5 | 43.14°C | 0.990 |
| 12.149V | 4.962V | 3.296V | 5.037V | 436.074 | 50.33°C | 115.16V | ||||
| 7 | 31.746A | 7.061A | 7.015A | 2.190A | 454.890 | 88.710% | 721 | 12.1 | 43.42°C | 0.990 |
| 12.152V | 4.958V | 3.293V | 5.024V | 512.786 | 51.29°C | 115.14V | ||||
| 8 | 36.355A | 8.075A | 8.024A | 2.397A | 520.202 | 87.961% | 1147 | 25.4 | 44.13°C | 0.991 |
| 12.152V | 4.955V | 3.290V | 5.008V | 591.399 | 52.69°C | 115.14V | ||||
| 9 | 41.378A | 8.584A | 8.514A | 2.401A | 585.134 | 87.263% | 1624 | 33.1 | 44.42°C | 0.992 |
| 12.147V | 4.952V | 3.289V | 5.000V | 670.543 | 53.68°C | 115.14V | ||||
| 10 | 46.144A | 9.093A | 9.034A | 3.014A | 649.987 | 86.376% | 2080 | 41.3 | 45.69°C | 0.992 |
| 12.142V | 4.950V | 3.287V | 4.977V | 752.513 | 55.49°C | 115.13V | ||||
| 11 | 51.491A | 9.098A | 9.037A | 3.019A | 714.815 | 85.500% | 2119 | 42.2 | 46.60°C | 0.992 |
| 12.140V | 4.948V | 3.286V | 4.969V | 836.038 | 56.80°C | 115.12V | ||||
| CL1 | 0.149A | 12.002A | 12.000A | 0.000A | 100.824 | 84.397% | 0 | <6.0 | 42.72°C | 0.977 |
| 12.175V | 4.960V | 3.290V | 5.100V | 119.464 | 49.14°C | 115.17V | ||||
| CL2 | 54.017A | 1.003A | 0.998A | 1.000A | 668.967 | 86.848% | 2105 | 41.3 | 45.70°C | 0.992 |
| 12.138V | 4.963V | 3.300V | 5.038V | 770.273 | 55.29°C | 115.12V |
The passive operation lasts long, and the PSU doesn't have a problem operating under very high ambient temperatures. The PF readings are also high, with 115V input.
20-80W Load Tests
In the following tests, we measure the PH-P650G'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 | 1.194A | 0.502A | 0.481A | 0.195A | 19.589 | 68.366% | 0 | <6.0 | 0.827 |
| 12.138V | 4.987V | 3.314V | 5.127V | 28.653 | 115.23V | ||||
| 2 | 2.450A | 1.004A | 0.995A | 0.391A | 40.035 | 79.531% | 0 | <6.0 | 0.927 |
| 12.139V | 4.980V | 3.310V | 5.120V | 50.339 | 115.17V | ||||
| 3 | 3.632A | 1.507A | 1.480A | 0.587A | 59.499 | 83.882% | 0 | <6.0 | 0.957 |
| 12.141V | 4.979V | 3.309V | 5.113V | 70.932 | 115.19V | ||||
| 4 | 4.881A | 2.011A | 1.995A | 0.784A | 79.888 | 86.352% | 0 | <6.0 | 0.968 |
| 12.144V | 4.978V | 3.308V | 5.106V | 92.514 | 115.14V |
We would like to see over 70% efficiency with 20W load, and above 80% with 40W.
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 | 0.925A | 0.205A | 0.204A | 0.051A | 13.168 | 58.493% | 0 | <6.0 | 0.767 |
| 12.115V | 4.991V | 3.318V | 5.130V | 22.512 | 115.18V |
With 2% of the PSU's max-rated-capacity load, the efficiency is low.
Efficiency
Next, we plotted a chart showing the PH-P650G’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 efficiency levels are not so high, in all load regions (super-light, light and normal).
5VSB Efficiency
| Test # | 5VSB | DC/AC (Watts) | Efficiency | PF/AC Volts |
| 1 | 0.100A | 0.514 | 73.219% | 0.111 |
| 5.133V | 0.702 | 115.17V | ||
| 2 | 0.250A | 1.283 | 75.872% | 0.225 |
| 5.129V | 1.691 | 115.17V | ||
| 3 | 0.550A | 2.818 | 77.058% | 0.343 |
| 5.122V | 3.657 | 115.17V | ||
| 4 | 1.000A | 5.113 | 77.212% | 0.420 |
| 5.112V | 6.622 | 115.17V | ||
| 5 | 1.500A | 7.651 | 76.810% | 0.457 |
| 5.100V | 9.961 | 115.17V | ||
| 6 | 3.000A | 15.184 | 75.524% | 0.499 |
| 5.061V | 20.105 | 115.14V |
The 5VSB rail is not efficient. Seasonic should fix this in an upcoming version of its Focus platform.
Power Consumption In Idle And Standby
| Mode | 12V | 5V | 3.3V | 5VSB | Watts | PF/AC Volts |
| Idle | 12.113V | 4.992V | 3.318V | 5.133V | 0.496 | |
| 9.222 | 115.2V | |||||
| Standby | 0.008 | |||||
| 0.047 | 115.2V |
The vampire power is low with both voltage inputs.
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 profile is relaxed, even at high operating temperatures.
The following results were obtained at 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit) ambient temperature.
Up to around 410W load at +12V, the PSU is dead silent. It needs more than 525W to enter the 30-35 dB(A) zone, and this for a short period.
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