Efficiency, Temperature And Noise
Efficiency
Our efficiency testing procedure is detailed here.
Using the previous page's results, we plotted a chart showing the ST60F-TI's efficiency at low loads and loads from 10 to 110 percent of the PSU's maximum-rated capacity.
Under light loads (<170W), efficiency is significantly higher with 115V input.
Efficiency At Low Loads
In the following tests, we measure the efficiency of the ST60F-TI 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 (RPM) | Fan Noise | PF/AC Volts |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1.226A | 0.491A | 0.475A | 0.195A | 19.62 | 75.46% | 705 | 26.0 dB(A) | 0.808 |
| 11.894V | 5.018V | 3.360V | 5.012V | 26.00 | 115.1V | ||||
| 2 | 2.477A | 0.990A | 0.982A | 0.396A | 39.72 | 84.82% | 705 | 26.0 dB(A) | 0.894 |
| 11.900V | 5.016V | 3.355V | 5.005V | 46.83 | 115.1V | ||||
| 3 | 3.729A | 1.487A | 1.489A | 4.998A | 59.82 | 91.40% | 705 | 26.0 dB(A) | 0.920 |
| 11.899V | 5.013V | 3.352V | 4.998V | 65.45 | 115.1V | ||||
| 4 | 4.974A | 1.994A | 1.970A | 0.800A | 79.75 | 91.91% | 730 | 26.2 dB(A) | 0.938 |
| 11.897V | 5.010V | 3.348V | 4.991V | 86.77 | 115.1V |
Efficiency is super high under light loads, and the fan's noise is kept at very low levels, as you can see in the table above.
5VSB Efficiency
The ATX specification states that 5VSB standby supply efficiency should be as high as possible, recommending 50 percent or higher efficiency with 100mA of load, 60 percent or higher with 250mA of load and 70 percent or higher with 1A or more of load.
We will 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 | 0.101A | 0.50 | 73.53% | 0.045 |
| 4.936V | 0.68 | 115.1V | ||
| 2 | 0.252A | 1.24 | 77.02% | 0.103 |
| 4.932V | 1.61 | 307.6V | ||
| 3 | 1.002A | 4.92 | 84.25% | 0.274 |
| 4.911V | 5.84 | 115.1V | ||
| 4 | 2.502A | 12.18 | 82.24% | 0.389 |
| 4.868V | 14.81 | 115.1V |
A Titanium-rated PSU ought to have a highly efficient 5VSB rail, and indeed that's the case here. Only FSP's HG650 registers notably higher efficiency than SilverStone's ST60F-TI, by isolating the APFC converter while the PSU is in standby mode.
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 | 11.901V | 5.024V | 3.364V | 5.024V | 7.76 | 0.448 |
| 115.1V | ||||||
| Standby | 0.06 | 0.004 | ||||
| 115.1V |
Phantom power is very low with both 115V and 230V input.
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 35 °C (95 °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 small, custom-made anechoic chamber with internals completely covered in sound-proofing material (be quiet! Noise Absorber kit). Background noise inside the chamber was below 18 dB(A) during testing, and the results were obtained with the PSU operating at 35 °C (95 °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 at 28 °C (82.4 °F) to 30 °C (86 °F).
Under normal temperature conditions, SilverStone's Titanium-class ST60F-TI features quiet operation. Even in worst-case scenario, the fan's output stays below 34 dB(A). Despite the lack of a semi-passive mode, this power supply appears ideal for low-noise configurations.