Efficiency

Using the efficiency results from the previous page, we plotted a chart to show the SuperNOVA 650 G2's efficiency at low loads and loads equal to 20%-100% of the PSU's maximum-rated load.



At low loads, efficiency was pretty high, while close to most of the competition at normal loads, with only the FSP Aurum 92+, a Platinum unit, and the Corsair CS650M well above the rest of the pack.

Efficiency at Low Loads

The next tests measure the SuperNOVA 650 G2's efficiency 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 PSU cracked the 80% mark in all four low-load tests, which nicely depicts the advantage of using a low-to-mid-capacity PSU with a system that consumes very little energy in idle and low utilization scenarios.

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 isn't that efficient since it failed to crack the 80% mark in these efficiency tests. We expect at least a reading in these tests to be above 80% with a Gold- or Platinum-certified unit.

Power Consumption in Idle & Standby

In the table below depicts the power consumption and voltage values of the rails (except -12V) when the PSU is in idle mode (powered on but without any load on its rails) and the power consumption numbers when the PSU is in standby mode (without any load at 5VSB).

Phantom power is low—the unit easily meets the ErP Lot 6 2013 requirements.

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 39°C-47°C ambient.



A chart that shows the cooling fan's speed (RPMs) and its output noise follows. We measure the fan's noise from one meter away, 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 39°C-47°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.



This is a truly silent PSU, and as you can see in the graph above, it operates in passive mode at up to 500-550 W.