Efficiency

Using the efficiency results on the previous page, we plotted a chart that shows the efficiency of the V1200 at low loads and at loads equal to 20%-110% of the PSU's maximum-rated load.



The V1200 performed pretty well at low loads, but the competition did even better. That said, the tide turned with normal loads as the V1200 managed to top the chart.

Efficiency at Low Loads

In the next tests, we measured the efficiency of the V1200 at loads much lower than 20% of its maximum-rated load (the lowest load the 80 Plus Standard measures). The loads we dialed were 40 W, 60 W, 80 W, and 100 W (for PSUs with over 500 W of capacity). This is important for settings where the PC is in idle mode with Power Saving turned on.

The V1200 operated in fanless mode in the first three tests, but the increasing temperature in our hot box made it engage the fan during the last test. We prefer relaxed semi-passive modes like this one over aggressive ones that engage the fan incredibly late, which puts a disproportionate amount of stress on such heat-sensitive components as electrolytic capacitors. The V1200 also managed to score a decent efficiency reading of close to 75% with 40 W and cracked the 80% mark pretty easily with 60 W.

5VSB Efficiency

The ATX specification states that 5VSB standby supply efficiency should be as high as possible and recommends 50% or higher efficiency with 100 mA of load, 60% or higher with 250 mA of load, and 70% or higher with 1 A or more of load.

We will take four measurements: one at 100, 250, and 1000 mA, each, and one with the full load the 5VSB rail can handle.

The 5VSB rail is quite efficient since it easily cracked the corresponding thresholds in our tests. It even cracked the 80% mark in the last test, which is not an easy feat by this rail's standards.

Power Consumption in Idle & Standby

In the table below, you will find the power consumption and the voltage values of all rails (except -12V) when the PSU is in idle mode (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).

The V1200 only consumes 0.17 W in standby, which makes it a very green (ECO friendly) PSU.

Fan RPM, Delta Temperature & Output Noise

The cooling fan's speed (RPMs) and the delta difference between input and output temperature are illustrated in the following chart. The following results were obtained at 38°C-45°C ambient.



A chart that shows the cooling fan's speed (RPMs) and the output noise follows. We measure fan noise at a distance of 1 meter, inside a small custom-made anechoic chamber whose internals are completely covered in specialized soundproofing material (Be Quiet! Noise Absorber Kit). Background noise inside the anechoic chamber was below 20 dBA during testing, and the results were obtained with the PSU operating at 38°C-45°C ambient.



The following graph illustrates the fan's output noise throughout the PSU's entire operating range. The same conditions of the above graph apply to our measurements, but the ambient temperature was in-between 28°C and 30°C.



We ran the above tests in automatic fan mode, and the PSU was, as you can see, pretty silent throughout most of its operational range, so you are better off picking auto instead of hybrid fan mode unless your hearing is incredibly sensitive. Providing internal PSU components with cooling by having the fan work at very low speeds throughout is always better than having the fan engage after temperatures surpass a specified threshold as auto fan mode significantly decreases how much stress components like electrolytic capacitors, which feature a lifetime that is highly dependent on their operational temperatures, have to endure.