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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 on all rails. If we didn't consider the voltage drop at 12V, this rail would have perfect load regulation at light loads (below 60W).
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 the required (17ms), 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.
Inrush current is high with 230V.
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 is high in our chart. Still, it is much lower than the limit (3.5mA).
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 |
10% | 6.444A | 2A | 1.999A | 0.982A | 99.993 | 86.811% | 0 | <6.0 | 44.43°C | 0.972 |
Row 2 - Cell 0 | 12.166V | 4.999V | 3.302V | 5.091V | 115.185 | Row 2 - Cell 6 | Row 2 - Cell 7 | Row 2 - Cell 8 | 40.21°C | 115.18V |
20% | 13.894A | 3.002A | 3A | 1.181A | 199.927 | 90.28% | 0 | <6.0 | 45.39°C | 0.969 |
Row 4 - Cell 0 | 12.166V | 4.997V | 3.299V | 5.079V | 221.452 | Row 4 - Cell 6 | Row 4 - Cell 7 | Row 4 - Cell 8 | 40.74°C | 115.17V |
30% | 21.719A | 3.504A | 3.503A | 1.381A | 299.954 | 91.729% | 0 | <6.0 | 46.21°C | 0.974 |
Row 6 - Cell 0 | 12.150V | 4.995V | 3.297V | 5.068V | 327.001 | Row 6 - Cell 6 | Row 6 - Cell 7 | Row 6 - Cell 8 | 41.01°C | 115.17V |
40% | 29.488A | 4.004A | 4.006A | 1.582A | 399.382 | 91.871% | 680 | 17.8 | 41.74°C | 0.979 |
Row 8 - Cell 0 | 12.147V | 4.995V | 3.294V | 5.058V | 434.719 | Row 8 - Cell 6 | Row 8 - Cell 7 | Row 8 - Cell 8 | 47.72°C | 115.14V |
50% | 36.938A | 5.008A | 5.012A | 1.784A | 499.088 | 91.39% | 1505 | 41.6 | 42.38°C | 0.982 |
Row 10 - Cell 0 | 12.145V | 4.992V | 3.292V | 5.044V | 546.111 | Row 10 - Cell 6 | Row 10 - Cell 7 | Row 10 - Cell 8 | 48.68°C | 115.13V |
60% | 44.442A | 6.014A | 6.019A | 1.987A | 599.619 | 90.979% | 1504 | 41.6 | 42.54°C | 0.985 |
Row 12 - Cell 0 | 12.147V | 4.988V | 3.289V | 5.033V | 659.075 | Row 12 - Cell 6 | Row 12 - Cell 7 | Row 12 - Cell 8 | 49.29°C | 115.12V |
70% | 51.875A | 7.021A | 7.028A | 2.19A | 699.345 | 90.41% | 1505 | 41.6 | 43.58°C | 0.986 |
Row 14 - Cell 0 | 12.149V | 4.986V | 3.287V | 5.02V | 773.523 | Row 14 - Cell 6 | Row 14 - Cell 7 | Row 14 - Cell 8 | 50.76°C | 115.11V |
80% | 59.377A | 8.002A | 8.035A | 2.293A | 799.228 | 89.72% | 1856 | 47.2 | 43.81°C | 0.988 |
Row 16 - Cell 0 | 12.150V | 4.984V | 3.284V | 5.012V | 890.805 | Row 16 - Cell 6 | Row 16 - Cell 7 | Row 16 - Cell 8 | 51.32°C | 115.1V |
90% | 67.196A | 8.53A | 8.528A | 2.397A | 899.128 | 89.027% | 1858 | 47.2 | 44.34°C | 0.989 |
Row 18 - Cell 0 | 12.154V | 4.981V | 3.282V | 5.003V | 1009.945 | Row 18 - Cell 6 | Row 18 - Cell 7 | Row 18 - Cell 8 | 52.43°C | 115.1V |
100% | 74.797A | 9.037A | 9.052A | 3.01A | 999.142 | 88.223% | 1859 | 47.2 | 45.81°C | 0.99 |
Row 20 - Cell 0 | 12.160V | 4.978V | 3.28V | 4.982V | 1132.525 | Row 20 - Cell 6 | Row 20 - Cell 7 | Row 20 - Cell 8 | 54.72°C | 115.09V |
110% | 82.322A | 10.046A | 10.158A | 3.014A | 1099.749 | 87.386% | 1858 | 47.2 | 46.67°C | 0.991 |
Row 22 - Cell 0 | 12.165V | 4.976V | 3.277V | 4.975V | 1258.498 | Row 22 - Cell 6 | Row 22 - Cell 7 | Row 22 - Cell 8 | 56.54°C | 115.08V |
CL1 | 0.113A | 15.076A | 15.074A | 0A | 126.267 | 82.487% | 1507 | 41.6 | 42.95°C | 0.979 |
Row 24 - Cell 0 | 12.187V | 4.994V | 3.29V | 5.102V | 153.074 | Row 24 - Cell 6 | Row 24 - Cell 7 | Row 24 - Cell 8 | 48.66°C | 115.15V |
CL2 | 0.113A | 24.997A | 0A | 0A | 126.375 | 80.784% | 1840 | 47.3 | 43.3°C | 0.976 |
Row 26 - Cell 0 | 12.166V | 5.001V | 3.294V | 5.106V | 156.437 | Row 26 - Cell 6 | Row 26 - Cell 7 | Row 26 - Cell 8 | 50.42°C | 115.14V |
CL3 | 0.113A | 0A | 25.059A | 0A | 83.862 | 75.048% | 1848 | 47.2 | 44.44°C | 0.969 |
Row 28 - Cell 0 | 12.162V | 4.996V | 3.292V | 5.103V | 111.745 | Row 28 - Cell 6 | Row 28 - Cell 7 | Row 28 - Cell 8 | 52.83°C | 115.14V |
CL4 | 82.312A | 0A | 0A | 0.001A | 999.741 | 89.049% | 1863 | 47.3 | 45.58°C | 0.989 |
Row 30 - Cell 0 | 12.146V | 4.986V | 3.29V | 5.061V | 1122.685 | Row 30 - Cell 6 | Row 30 - Cell 7 | Row 30 - Cell 8 | 54.83°C | 115.08V |
Similar to the 1000 G6, the passive operation lasts up to 30% load, and with 40% load, the PSU's fan spins at low RPM. The fan speed is high in all other tests, leading to increased noise output.
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]) | Temps (In/Out) | PF/AC Volts |
20W | 1.226A | 0.5A | 0.499A | 0.196A | 19.994 | 76.592% | 0 | <6.0 | 39.42°C | 0.789 |
Row 2 - Cell 0 | 12.101V | 5.004V | 3.306V | 5.115V | 26.105 | Row 2 - Cell 6 | Row 2 - Cell 7 | Row 2 - Cell 8 | 37.14°C | 115.19V |
40W | 2.700A | 0.699A | 0.699A | 0.293A | 39.993 | 82.924% | 0 | <6.0 | 40.35°C | 0.918 |
Row 4 - Cell 0 | 12.107V | 5.004V | 3.305V | 5.111V | 48.228 | Row 4 - Cell 6 | Row 4 - Cell 7 | Row 4 - Cell 8 | 37.73°C | 115.19V |
60W | 4.154A | 0.9A | 0.899A | 0.392A | 59.993 | 83.417% | 0 | <6.0 | 41.58°C | 0.948 |
Row 6 - Cell 0 | 12.163V | 5.002V | 3.304V | 5.108V | 71.919 | Row 6 - Cell 6 | Row 6 - Cell 7 | Row 6 - Cell 8 | 38.42°C | 115.19V |
80W | 5.616A | 1.1A | 1.099A | 0.49A | 79.95 | 85.612% | 0 | <6.0 | 42.97°C | 0.959 |
Row 8 - Cell 0 | 12.165V | 5.001V | 3.303V | 5.104V | 93.387 | Row 8 - Cell 6 | Row 8 - Cell 7 | Row 8 - Cell 8 | 39.33°C | 115.18V |
Efficiency is high at light loads.
2% or 10W Load Test
From July 2020, the ATX spec requires 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.
12V | 5V | 3.3V | 5VSB | DC/AC (Watts) | Efficiency | Fan Speed (RPM) | PSU Noise (dB[A]) | Temps (In/Out) | PF/AC Volts |
1.463A | 0.264A | 0.264A | 0.053A | 20.153 | 76.834% | 0 | <6.0 | 29.5°C | 0.796 |
Row 2 - Cell 0 | 12.088V | 5.009V | 3.306V | 5.118V | 26.23 | Row 2 - Cell 6 | Row 2 - Cell 7 | 29.31°C | 115.15V |
The PSU achieves an impressive efficiency score with 2% of its max-rated capacity.
Efficiency and 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.
With normal loads, efficiency needs a boost. On the contrary, the unit achieves impressive efficiency results at light loads. Lastly, the APFC converter needs tuning for higher PF readings, especially with 230V input.
5VSB Efficiency
Test # | 5VSB | DC/AC (Watts) | Efficiency | PF/AC Volts |
1 | 0.1A | 0.512W | 72.332% | 0.064 |
Row 2 - Cell 0 | Row 2 - Cell 1 | 5.119V | 0.708W | 115.14V |
2 | 0.25A | 1.278W | 75.88% | 0.144 |
Row 4 - Cell 0 | Row 4 - Cell 1 | 5.115V | 1.684W | 115.14V |
3 | 0.55A | 2.809W | 77.344% | 0.263 |
Row 6 - Cell 0 | Row 6 - Cell 1 | 5.108V | 3.632W | 115.14V |
4 | 1A | 5.098W | 77.777% | 0.365 |
Row 8 - Cell 0 | Row 8 - Cell 1 | 5.098V | 6.554W | 115.15V |
5 | 1.5A | 7.629W | 77.581% | 0.425 |
Row 10 - Cell 0 | Row 10 - Cell 1 | 5.086V | 9.834W | 115.15V |
6 | 2.999A | 15.114W | 75.733% | 0.502 |
Row 12 - Cell 0 | Row 12 - Cell 1 | 5.04V | 19.958W | 115.15V |
The 5VSB rail is not efficient, and this is a great shame. Seasonic must upgrade the 5VSB circuit in its Focus platform.
Power Consumption In Idle and Standby
Mode | 12V | 5V | 3.3V | 5VSB | Watts | PF/AC Volts |
Idle | 12.083V | 5.01V | 3.307V | 5.121V | 2.966 | 0.211 |
Row 2 - Cell 0 | Row 2 - Cell 1 | Row 2 - Cell 2 | Row 2 - Cell 3 | Row 2 - Cell 4 | Row 2 - Cell 5 | 115.14V |
Standby | Row 3 - Cell 1 | Row 3 - Cell 2 | Row 3 - Cell 3 | Row 3 - Cell 4 | 0.059 | 0.005 |
Row 4 - Cell 0 | Row 4 - Cell 1 | Row 4 - Cell 2 | Row 4 - Cell 3 | Row 4 - Cell 4 | Row 4 - Cell 5 | 115.14V |
Vampire power is increased 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 is aggressive in harsh conditions. The compact dimensions of the platform and the relatively small fan, along with the extended warranty, don't leave much room for a lore relaxed speed profile.
The following results were obtained at 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit) ambient temperature.
At normal operating temperatures, close to 30 degrees Celsius, the PSU passive operation lasts for quite long, as long as you don't push the minor rails above 80W. Nonetheless, even at lower ambient, the fan's speed increases suddenly once the load exceeds 650W, with the noise output surpassing 35 dBA. Seasonic should improve the fan profile, offering more speed modes.
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Current page: Load Regulation, Hold-Up Time, Inrush and Leakage Current, Efficiency and Noise
Prev Page Specifications and Part Analysis Next Page Protection Features, DC Power Sequencing, Cross-Load Tests and Infrared ImagesAris Mpitziopoulos is a contributing editor at Tom's Hardware, covering PSUs.
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