Home / Tech News / Featured Tech Reviews / Riotoro 1200W Builder Edition PSU Review

Riotoro 1200W Builder Edition PSU Review


Our efficiency testing procedure is detailed here.

Using results from the previous page, we plotted a chart showing the PR-GP1200FM’s efficiency at low loads, and loads from 10 to 110 percent of its maximum-rated capacity.

The majority of the competing products in this capacity range feature higher efficiency certifications and cost more. So it is natural for the Riotoro offering to be at the bottom of the normal-load average efficiency chart. The unit takes over first place though, in the light loads chart.

Efficiency At Low Loads

In the following tests, we measure the PR-GP1200FM’s efficiency at loads significantly lower than 10 percent of its maximum capacity (the lowest load the 80 PLUS standard measures). The loads we dial are 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) PSU Noise (dB[A]) PF/AC Volts
1 1.192A 0.497A 0.479A 0.199A 19.458 64.642% 750 18.3 0.859
12.051V 5.029V 3.329V 5.022V 30.101 115.10V
2 2.455A 0.995A 0.989A 0.399A 39.870 77.368% 750 18.3 0.934
12.047V 5.026V 3.331V 5.013V 51.533 115.11V
3 3.651A 1.490A 1.471A 5.013A 59.384 83.305% 753 18.3 0.960
12.048V 5.034V 3.327V 5.013V 71.285 115.10V
4 4.914A 1.987A 1.985A 0.800A 79.782 85.820% 753 18.3 0.970
12.044V 5.031V 3.324V 5.002V 92.964 115.10V

With light loads the 1.2kW unit goes pretty well, while at the same time the fan’s noise is kept low.

5VSB Efficiency

The ATX specification (revision 1.4), along with CEC, ErP Lot 3 2014 and ErP Lot 6 2010/2013, states that the 5VSB standby supply efficiency should be as high as possible, recommending 75 percent or higher with 550mA, 1A, and 1.5A of load.

The supply 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
Efficiency PF/AC Volts
1 0.100A 0.510 70.442% 0.084
5.097V 0.724 115.12V
2 0.250A 1.273 75.459% 0.176
5.092V 1.687 115.11V
3 0.550A 2.796 79.140% 0.290
5.083V 3.533 115.11V
4 1.000A 5.070 79.405% 0.376
5.069V 6.385 115.12V
5 1.500A 7.582 79.618% 0.423
5.054V 9.523 115.10V
6 3.000A 15.002 78.030% 0.479
5.000V 19.226 115.10V


The 5vSB rail’s efficiency is satisfactory, although the majority of the (more expensive) offerings achieve better results here.

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 unit is in standby mode (without any load, at 5VSB).

Mode 12V 5V 3.3V 5VSB Watts PF/AC Volts
Idle 12.064V 5.024V 3.334V 5.025V 10.043 0.552
Standby 0.078 0.009

The vampire power is a bit higher than expected, especially with 230V. This affects the 5VSB’s efficiency under very light loads.

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 45°C (113°F) ambient temperature.

The next chart shows the fan’s speed (again, in RPM) and output noise. We measure acoustics from one meter away, inside a hemi-anechoic chamber. Background noise inside the chamber is below 6 dB(A) during testing (it’s actually much lower, but our sound meter’s microphone hits its floor), and the results are obtained with the PSU operating at 37°C (98.6°F) to 45°C (113°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 is between 30°C (86°F) to 32°C (89.6°F).

If we take into account the fan control circuit’s behaviour under high operating temperatures, we expected it to be more relaxed under normal operating temperatures. Nonetheless, this is a high capacity unit so it needs to have proper airflow to ensure the internal components take the least amount of stress, in order to maximise lifespan.

With up to 290W at +12V the PSU is silent, while with up to 610W it will probably stay below most user’s noise radar. In the worst case scenario, which is over 970W load at +12V, the fan’s noise barely exceeds 40 dB(A).

Become a Patron!

Check Also

ASRock X570 Taichi Motherboard Review

It's ASRock's £300 X570 offering - what does Luke make of it?