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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.
Results 1-8: Load Regulation
The load regulation is tight on all 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 hold-up time is longer than 17ms, while 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.
Results 13-14: Inrush Current
The inrush current is low, with both voltage inputs.
10-110% Load Tests
These tests reveal the TPG-0850F1FAP'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 | 5.275A | 1.980A | 1.972A | 0.992A | 84.971 | 87.683% | 0 | <6.0 | 45.25°C | 0.971 |
12.038V | 5.053V | 3.279V | 5.040V | 96.907 | 40.07°C | 115.15V | ||||
2 | 11.518A | 2.974A | 2.973A | 1.192A | 169.464 | 91.016% | 0 | <6.0 | 46.22°C | 0.991 |
12.038V | 5.049V | 3.294V | 5.035V | 186.191 | 40.21°C | 115.15V | ||||
3 | 18.169A | 3.472A | 3.475A | 1.393A | 254.615 | 92.107% | 0 | <6.0 | 47.29°C | 0.995 |
12.031V | 5.045V | 3.310V | 5.028V | 276.433 | 41.01°C | 115.15V | ||||
4 | 24.815A | 3.969A | 3.990A | 1.593A | 339.834 | 91.741% | 1392 | 39.0 | 41.98°C | 0.997 |
12.034V | 5.041V | 3.309V | 5.022V | 370.429 | 48.86°C | 115.15V | ||||
5 | 31.138A | 4.966A | 4.976A | 1.794A | 425.124 | 91.926% | 792 | 21.7 | 42.01°C | 0.997 |
12.033V | 5.038V | 3.300V | 5.017V | 462.461 | 49.49°C | 115.17V | ||||
6 | 37.403A | 5.957A | 5.987A | 1.996A | 509.640 | 91.669% | 836 | 23.5 | 42.26°C | 0.997 |
12.027V | 5.035V | 3.307V | 5.011V | 555.954 | 50.29°C | 115.17V | ||||
7 | 43.719A | 6.961A | 7.009A | 2.199A | 594.971 | 90.952% | 1388 | 38.8 | 43.28°C | 0.997 |
12.028V | 5.030V | 3.296V | 5.004V | 654.157 | 51.78°C | 115.16V | ||||
8 | 50.038A | 7.960A | 8.016A | 2.401A | 680.321 | 90.178% | 1394 | 39.2 | 43.89°C | 0.998 |
12.029V | 5.026V | 3.294V | 4.999V | 754.420 | 52.78°C | 115.17V | ||||
9 | 56.785A | 8.463A | 8.507A | 2.402A | 765.243 | 89.699% | 1396 | 39.2 | 44.54°C | 0.998 |
12.023V | 5.023V | 3.292V | 4.997V | 853.127 | 53.89°C | 115.19V | ||||
10 | 63.293A | 8.968A | 9.028A | 3.011A | 850.056 | 89.166% | 1401 | 39.2 | 45.57°C | 0.998 |
12.013V | 5.019V | 3.290V | 4.983V | 953.337 | 55.88°C | 115.18V | ||||
11 | 70.417A | 8.976A | 9.032A | 3.013A | 934.871 | 88.669% | 1403 | 39.3 | 46.63°C | 0.998 |
12.002V | 5.016V | 3.288V | 4.980V | 1054.334 | 57.74°C | 115.19V | ||||
CL1 | 0.157A | 12.001A | 12.002A | 0.000A | 102.112 | 83.317% | 1374 | 38.5 | 41.84°C | 0.831 |
12.031V | 5.043V | 3.308V | 5.061V | 122.558 | 49.73°C | 115.19V | ||||
CL2 | 70.841A | 1.004A | 1.000A | 1.000A | 865.073 | 89.591% | 1401 | 39.2 | 45.28°C | 0.998 |
12.023V | 5.025V | 3.294V | 5.014V | 965.580 | 55.39°C | 115.18V |
With 40% load the fan spins at high speeds, to remove the excess heat from the internals, while with 50% load it drops to much lower speeds. This is not an optimal fan speed profile and we would highly prefer the fan to engage sooner, rather than latter and at such high speeds.
Thanks to the digitally controlled PFC the PF readings are high, even at lower loads. Moreover, the PSU meets the 80 PLUS Platinum requirements with 20% and 100% load levels, and it is very close with 50%. Under lower operating temperatures you should expect even higher efficiency levels.
20-80W Load Tests
In the following tests, we measure the TPG-0850F1FAP'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 | 1.202A | 0.495A | 0.483A | 0.198A | 19.592 | 68.289% | 0 | <6.0 | 0.720 |
12.053V | 5.058V | 3.312V | 5.056V | 28.690 | 115.15V | ||||
2 | 2.463A | 0.989A | 0.996A | 0.396A | 39.989 | 79.457% | 0 | <6.0 | 0.789 |
12.054V | 5.056V | 3.312V | 5.053V | 50.328 | 115.15V | ||||
3 | 3.674A | 1.484A | 1.449A | 0.594A | 59.520 | 84.671% | 0 | <6.0 | 0.813 |
12.039V | 5.055V | 3.304V | 5.049V | 70.296 | 115.16V | ||||
4 | 4.953A | 1.980A | 1.912A | 0.793A | 79.916 | 86.895% | 0 | <6.0 | 0.827 |
12.039V | 5.053V | 3.285V | 5.044V | 91.968 | 115.17V |
The fan doesn't engage at all, at light loads. It would be nice to see higher than 70% efficiency with 20W load, and over 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 | 1.202A | 0.495A | 0.483A | 0.198A | 19.592 | 68.289% | 0 | <6.0 | 0.720 |
12.053V | 5.058V | 3.312V | 5.056V | 28.690 | 115.15V | ||||
2 | 2.463A | 0.989A | 0.996A | 0.396A | 39.989 | 79.457% | 0 | <6.0 | 0.789 |
12.054V | 5.056V | 3.312V | 5.053V | 50.328 | 115.15V | ||||
3 | 3.674A | 1.484A | 1.449A | 0.594A | 59.520 | 84.671% | 0 | <6.0 | 0.813 |
12.039V | 5.055V | 3.304V | 5.049V | 70.296 | 115.16V | ||||
4 | 4.953A | 1.980A | 1.912A | 0.793A | 79.916 | 86.895% | 0 | <6.0 | 0.827 |
12.039V | 5.053V | 3.285V | 5.044V | 91.968 | 115.17V |
With 2%, of the PSU's max-rated-capacity we measure well over 60% efficiency. Still the ATX spec will require for more than 70%, from July 2020.
Efficiency
Next, we plotted a chart showing the TPG-0850F1FAP’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.
Results 15-18: Efficiency
The unit fares well against the similar spec competition, in all load levels (super light, light and normal).
5VSB Efficiency
Test # | 5VSB | DC/AC (Watts) | Efficiency | PF/AC Volts |
1 | 0.100A | 0.502 | 75.831% | 0.053 |
5.016V | 0.662 | 115.16V | ||
2 | 0.250A | 1.254 | 77.743% | 0.124 |
5.013V | 1.613 | 115.16V | ||
3 | 0.550A | 2.755 | 78.356% | 0.238 |
5.008V | 3.516 | 115.16V | ||
4 | 1.000A | 5.000 | 77.375% | 0.349 |
4.999V | 6.462 | 115.16V | ||
5 | 1.500A | 7.486 | 77.319% | 0.415 |
4.989V | 9.682 | 115.16V | ||
6 | 3.001A | 14.880 | 76.899% | 0.492 |
4.959V | 19.350 | 115.16V |
Results 19-20: 5VSB Efficiency
We have seen better 5VSB circuits from CWT. This is a high-end platform, so we expected one of CWT's "good" 5VSB regulator circuits to be utilized.
Power Consumption In Idle And Standby
Mode | 12V | 5V | 3.3V | 5VSB | Watts | PF/AC Volts |
Idle | 12.072V | 5.060V | 3.312V | 5.061V | 8.366 | 0.429 |
115.2V | ||||||
Standby | 0.038 | 0.003 | ||||
115.2V |
Results 21-22: Vampire Power
The vampire power levels stay low, with both 115V and 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 registers a peak with a 340W load, at 42 degrees Celsius, and it drops at lower speeds with up to 510W load. With higher loads and with the ambient temperature exceeding 43 degrees Celsius, the fan spins at full speed, with the noise output being close to 40 dB(A).
The following results were obtained at 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit) ambient temperature.
The fan speed profile is not optimal, even at normal operating temperatures. There is no need for the fan to spin at full speed, right after the end of its passive mode. It is way better for the passive mode to last less time and engage the fan at lower speeds afterward.
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Current page: Load Regulation, Hold-Up Time, Inrush 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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