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Efficiency, Temperature & Noise
Efficiency
Our efficiency testing procedure is detailed here.
Using results from the previous page, we plotted a chart showing the 650 G3’s efficiency at low loads, and loads from 10 to 110 percent of its maximum-rated capacity.
Under normal loads, EVGA's 650 G3 is on par with Corsair's RM650x. Under light loads, it lands in second place behind the Seasonic SSR-650PD, which is 80 PLUS Platinum-certified.
Efficiency At Low Loads
In the following tests, we measure the PSU's efficiency at loads significantly lower than 10 percent of its maximum capacity (the lowest load the 80 PLUS standard measures). The loads we dialed were 20, 40, 60, and 80W. 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 | PSU Noise | PF/AC Volts |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1.194A | 0.492A | 0.484A | 0.196A | 19.662 | 76.319% | 0 RPM | <6.0 dB(A) | 0.729 |
| 12.229V | 5.013V | 3.308V | 5.068V | 25.763 | 115.10V | ||||
| 2 | 2.412A | 0.990A | 0.994A | 0.396A | 39.745 | 83.797% | 0 RPM | <6.0 dB(A) | 0.872 |
| 12.225V | 5.015V | 3.309V | 5.061V | 47.430 | 157.55V | ||||
| 3 | 3.632A | 1.487A | 1.508A | 5.056A | 59.864 | 85.388% | 1462 RPM | 37.8 dB(A) | 0.945 |
| 12.233V | 5.016V | 3.310V | 5.056V | 70.108 | 115.10V | ||||
| 4 | 4.841A | 1.995A | 1.990A | 0.791A | 79.818 | 86.888% | 1355 RPM | 33.5 dB(A) | 0.941 |
| 12.234V | 5.017V | 3.311V | 5.050V | 91.863 | 115.10V |
This PSU's efficiency is high under light loads. But once the fan starts spinning fast to exhaust heat, its noise output ramps up as well.
5VSB Efficiency
The ATX specification, along with CEC, ErP Lot 3 2014 and ErP Lot 6 2010/2013, states that 5VSB standby supply efficiency should be as high as possible, recommending 75 percent or higher with 550mA, 1A, and 1.5A of load. The PSU should also achieve higher than 75% efficiency at 5VSB under full load, or with 3A if its max current output on this rail is higher than 3A.
We take six measurements: one each at 100, 250, 550, 1000, and 1500mA, and one with the full load the 5VSB rail can handle.
| Test # | 5VSB | DC/AC (Watts) | Efficiency | PF/AC Volts |
|---|---|---|---|---|
| 1 | 0.102A | 0.515 | 73.153% | 0.051 |
| 5.070V | 0.704 | 115.05V | ||
| 2 | 0.252A | 1.277 | 76.789% | 0.114 |
| 5.066V | 1.663 | 115.05V | ||
| 3 | 0.543A | 2.744 | 77.955% | 0.212 |
| 5.058V | 3.520 | 115.05V | ||
| 4 | 1.002A | 5.058 | 78.467% | 0.311 |
| 5.046V | 6.446 | 115.05V | ||
| 5 | 1.502A | 7.560 | 78.156% | 0.374 |
| 5.034V | 9.673 | 115.06V | ||
| 6 | 3.002A | 14.957 | 76.040% | 0.457 |
| 4.983V | 19.670 | 115.05V |
The 5VSB rail isn't particularly efficient. Super Flower has to improve its performance if the company wants to meet all ErP Lot 3 2014, ErP Lot 6 2013 and CEC regulations, which are very strict.
Power Consumption In Idle And Standby
In the table below, you'll find the power consumption and voltage values of all rails (except -12V) when the PSU is idle (powered on, but without any load on its rails), and the power consumption when the PSU is in standby mode (without any load, at 5VSB).
| Mode | 12V | 5V | 3.3V | 5VSB | Watts | PF/AC Volts |
|---|---|---|---|---|---|---|
| Idle | 12.230V | 5.012V | 3.308V | 5.074V | 4.608 | 0.267 |
| 115.1V | ||||||
| Standby | 0.07 | 0.005 | ||||
| 115.1V |
Vampire power is low enough at 115V, though it could be lower with 230V input. This would definitely help improve the 5VSB rail's efficiency.
Fan RPM, Delta Temperature, And Output Noise
Our mixed noise testing is described in detail here.
The first chart below illustrates the cooling fan's speed (in RPM), and the delta between input and output temperature. The results were obtained at 37°C (98.6°F) to 46°C (114.8°F) ambient temperature.
The next chart shows the cooling fan's speed (again, in RPM) and output noise. We measured acoustics from one meter away, inside a hemi-anechoic chamber. Background noise inside the chamber was below 6 dB(A) during testing (it's actually much lower, but our sound meter’s microphone hits its floor), and the results were obtained with the PSU operating at 37°C (98.6°F) to 46°C (114.8°F) ambient temperature.
The following graph illustrates the fan's output noise over the PSU's operating range. The same conditions of the above graph apply to our measurements, though the ambient temperature was between 30°C (86°F) to 32°C (89.6°F).
The semi-passive mode doesn't last long. Afterwards, the PSU's fan lands in a range between 25-30 dB(A). Super Flower could use a more granular ramp-up starting with lower RPM. This would help being noise output down at lighter loads.
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