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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. At the same time, it also applies less stress to the DC-DC converters that many system components utilize.
Results 1-8: Load Regulation
Unfortunately, the Ion Gold 850W's load regulation is far from tight, especially on the minor rails.
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.
Results 9-12: Hold-Up Time
The Ion Gold 850W's hold-up time doesn't reach the 17ms mark, and the power ok signal is also notably lower than 16ms.
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.
Results 13-14: Inrush Current
The Ion Gold 850W's inrush current is low with 115V input, but quite high with 230V input.
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 conduct the test with 253-264V input). The maximum acceptable limit of a leakage current is 3.5 mA. This 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.
The Ion Gold 850W's leakage current is appropriately low.
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 | 5.242A | 2.006A | 2.003A | 1.008A | 84.961 | 86.660% | 589 | 13.8 | 40.34°C | 0.968 |
12.086V | 4.985V | 3.297V | 4.963V | 98.039 | 44.29°C | 115.19V | ||||
2 | 11.520A | 3.019A | 3.007A | 1.214A | 170.041 | 91.128% | 592 | 14.0 | 40.57°C | 0.989 |
12.078V | 4.968V | 3.293V | 4.944V | 186.595 | 45.35°C | 115.19V | ||||
3 | 18.157A | 3.534A | 3.515A | 1.422A | 255.052 | 91.467% | 595 | 13.6 | 41.61°C | 0.996 |
12.061V | 4.954V | 3.286V | 4.925V | 278.845 | 46.89°C | 115.17V | ||||
4 | 24.806A | 4.041A | 4.027A | 1.628A | 340.065 | 91.218% | 599 | 13.5 | 41.87°C | 0.996 |
12.048V | 4.949V | 3.278V | 4.916V | 372.803 | 47.78°C | 115.16V | ||||
5 | 31.131A | 5.060A | 5.045A | 1.835A | 425.048 | 90.726% | 603 | 13.7 | 42.64°C | 0.997 |
12.031V | 4.941V | 3.272V | 4.906V | 468.494 | 49.66°C | 115.16V | ||||
6 | 37.429A | 6.070A | 6.068A | 2.001A | 509.413 | 89.994% | 792 | 22.0 | 42.66°C | 0.998 |
12.017V | 4.943V | 3.264V | 4.907V | 566.052 | 50.16°C | 115.14V | ||||
7 | 43.825A | 7.110A | 7.092A | 2.253A | 594.944 | 89.149% | 960 | 28.5 | 43.06°C | 0.998 |
11.998V | 4.925V | 3.259V | 4.883V | 667.362 | 51.06°C | 115.19V | ||||
8 | 50.236A | 8.003A | 8.118A | 2.463A | 679.619 | 88.198% | 1185 | 34.3 | 43.94°C | 0.999 |
11.981V | 4.916V | 3.252V | 4.872V | 770.557 | 52.53°C | 115.20V | ||||
9 | 57.078A | 8.658A | 8.622A | 2.466A | 765.224 | 87.320% | 1437 | 39.8 | 44.58°C | 0.999 |
11.961V | 4.910V | 3.247V | 4.869V | 876.343 | 53.57°C | 115.16V | ||||
10 | 63.658A | 9.183A | 9.162A | 3.099A | 850.055 | 86.211% | 1584 | 42.4 | 45.65°C | 0.999 |
11.944V | 4.902V | 3.242V | 4.842V | 986.016 | 55.00°C | 115.18V | ||||
11 | 70.848A | 9.204A | 9.192A | 3.106A | 934.713 | 85.342% | 1586 | 42.5 | 46.58°C | 0.999 |
11.927V | 4.890V | 3.231V | 4.830V | 1095.254 | 56.43°C | 115.17V | ||||
CL1 | 0.117A | 14.001A | 13.999A | 0.000A | 116.635 | 82.198% | 604 | 14.1 | 42.92°C | 0.982 |
12.085V | 4.954V | 3.276V | 5.018V | 141.895 | 49.57°C | 115.20V | ||||
CL2 | 70.796A | 0.999A | 1.001A | 1.000A | 859.777 | 86.959% | 1572 | 42.3 | 45.72°C | 0.999 |
11.960V | 4.917V | 3.250V | 4.892V | 988.717 | 55.17°C | 115.17V |
The PSU can easily handle high operating temperatures, and its APFC converter performs amazingly well, achieving high PF readings even at lower 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 | 1.227A | 0.500A | 0.498A | 0.200A | 19.994 | 64.120% | 584 | 14.0 | 0.865 |
12.101V | 5.003V | 3.302V | 5.001V | 31.182 | 115.18V | ||||
2 | 2.454A | 1.000A | 1.000A | 0.401A | 39.984 | 74.619% | 585 | 14.0 | 0.932 |
12.098V | 4.998V | 3.297V | 4.991V | 53.584 | 115.19V | ||||
3 | 3.686A | 1.503A | 1.503A | 0.603A | 60.013 | 83.514% | 586 | 13.8 | 0.952 |
12.089V | 4.992V | 3.292V | 4.980V | 71.860 | 115.19V | ||||
4 | 4.911A | 2.006A | 2.001A | 0.805A | 79.961 | 86.198% | 588 | 13.8 | 0.966 |
12.087V | 4.986V | 3.298V | 4.971V | 92.764 | 115.19V |
The Ion Gold 850W's efficiency readings are low with 20W and 40W loads. On the plus side, the fan spins at low speeds under light loads, so its noise output won't be a problem.
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 | 0.252A | 0.052A | 17.124 | 61.293% | 565 | 13.5 | 0.842 |
12.074V | 5.005V | 3.310V | 5.005V | 27.938 | 115.18V |
This is a new PSU model, so it should meet the over 70% efficiency requirement of the newer ATX specs.
Efficiency & Power Factor
Next, we plotted a chart showing the PSU’s efficiency at both low loads and loads ranging from 10 to 110% of its maximum rated capacity. The higher a PSU’s efficiency, the less energy gets wasted, leading to a reduced carbon footprint and lower electricity bills. The same goes for power factor.
Results 15-18: Efficiency
This PSU's average efficiency is satisfactory with normal loads, but this is not the case for light and super-light loads, where the Fractal PSU consistently takes last place in the corresponding charts. On the other hand, the power factor readings are high.
5VSB Efficiency
Test # | 5VSB | DC/AC (Watts) | Efficiency | PF/AC Volts |
1 | 0.100A | 0.510 | 69.293% | 0.107 |
5.094V | 0.736 | 115.16V | ||
2 | 0.250A | 1.273 | 75.504% | 0.219 |
5.089V | 1.686 | 115.16V | ||
3 | 0.550A | 2.793 | 77.027% | 0.363 |
5.078V | 3.626 | 115.16V | ||
4 | 1.000A | 5.062 | 77.412% | 0.459 |
5.061V | 6.539 | 115.16V | ||
5 | 1.500A | 7.565 | 77.320% | 0.505 |
5.042V | 9.784 | 115.15V | ||
6 | 3.000A | 14.946 | 76.670% | 0.550 |
4.982V | 19.494 | 115.15V |
Results 19-20: 5VSB Efficiency
The Ion Gold is on the extreme low end compared to other 850W PSUs here. We would like to see a more efficient 5VSB rail from this unit.
Power Consumption In Idle And Standby
Mode | 12V | 5V | 3.3V | 5VSB | Watts | PF/AC Volts |
Idle | 12.064V | 5.007V | 3.312V | 5.007V | 7.477 | 0.491 |
115.2V | ||||||
Standby | 0.101 | 0.014 | ||||
115.2V |
Results 21-22: Vampire Power
Vampire power, which refers to the amount of power a PSU uses while not doing anything, is unfortunately high here when compared to other 850W PSUs.
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 ramps up smoothly, even under highly-stressful conditions.
The following results were obtained between 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit) ambient temperature.
Under normal temperatures, the fan speed profile for this unit is unusual, especially with higher than 700W loads. There is a region where the noise exceeds 35 dBA, but with increased load on the minor rails, it drops below even 30 dBA. We'd guess that increased loads at 12V affect the fan's speed more than the combined load on the minor rails.
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Current page: Load Regulation, Hold-Up Time, Inrush & 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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