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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 L10-CM-600's efficiency at low loads, and loads from 10 to 110 percent of its maximum-rated capacity.
be quiet!'s L10-CM-600 comes close to Corsair's mid-level TX550M (which is 80 PLUS Gold-certified, but achieves the same ETA-C rating). Under light loads, the lower-capacity Pure Power 10 500W naturally achieves a higher overall efficiency level.
Efficiency At Low Loads
In the following tests, we measure the efficiency of be-quiet!'s L10-CM-600 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 | Fan Noise | PF/AC Volts |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1.198A | 0.491A | 0.472A | 0.196A | 19.632 | 68.089% | 568 RPM | 17.4 dB(A) | 0.580 |
| 12.155V | 5.057V | 3.368V | 5.083V | 28.833 | 115.14V | ||||
| 2 | 2.428A | 0.981A | 0.978A | 0.390A | 39.731 | 79.481% | 568 RPM | 17.4 dB(A) | 0.745 |
| 12.152V | 5.053V | 3.364V | 5.076V | 49.988 | 115.14V | ||||
| 3 | 3.659A | 1.477A | 1.484A | 5.069A | 59.887 | 84.020% | 568 RPM | 17.4 dB(A) | 0.964 |
| 12.148V | 5.050V | 3.362V | 5.069V | 71.277 | 115.14V | ||||
| 4 | 4.876A | 1.978A | 1.959A | 0.787A | 79.765 | 86.006% | 568 RPM | 17.4 dB(A) | 0.969 |
| 12.141V | 5.051V | 3.363V | 5.064V | 92.743 | 115.12V |
We would like to see higher efficiency during the first two light load tests. Efficiency is satisfying in the other two tests, though.
Across all of the tests, the fan spins at low speeds, operating almost silently.
5VSB Efficiency
The ATX specification states that 5VSB standby supply efficiency should be as high as possible, recommending 50 percent or higher with 100mA of load, 60 percent or higher with 250mA of load, and 70 percent or higher with 1A or more of load.
We take four measurements: one each at 100, 250, and 1000mA, and one with the full load the 5VSB rail can handle.
| Test # | 5VSB | DC/AC (Watts) | Efficiency | PF/AC Volts |
|---|---|---|---|---|
| 1 | 0.102A | 0.516 | 73.088% | 0.125 |
| 5.089V | 0.706 | 115.10V | ||
| 2 | 0.252A | 1.280 | 78.479% | 0.233 |
| 5.086V | 1.631 | 115.11V | ||
| 3 | 0.532A | 2.702 | 79.752% | 0.324 |
| 5.080V | 3.388 | 115.10V | ||
| 4 | 1.002A | 5.080 | 80.956% | 0.378 |
| 5.069V | 6.275 | 115.10V | ||
| 5 | 1.502A | 7.597 | 80.862% | 0.406 |
| 5.059V | 9.395 | 115.10V | ||
| 6 | 3.001A | 15.084 | 79.111% | 0.449 |
| 5.026V | 19.067 | 115.10V |
The 5VSB rail is highly efficient, meeting all ErP Lot 3/6 and CEC (California Energy Commission) requirements.
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 | 12.159V | 5.059V | 3.370V | 5.091V | 8.598 | 0.477 |
| 115.1V | ||||||
| Standby | 0.098 | 0.020 | ||||
| 115.1V |
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 16.6 dB(A) during testing. It's actually quite a bit lower, but our sound meter's mic is at its limit there. The ambient temperature was between 37°C (98.6°F) to 46°C (114.8°F).
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 at 30°C (86°F) to 32°C (89.6°F).
This is a quiet PSU, no doubt about it. With up to 490W loads, the output noise is kept close to 17 dB(A). Only with loads exceeding 500W does the PSU generate close to 28 dB(A).
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