Efficiency

Using the efficiency results on the previous page, we plotted a chart that shows the Edison M-650's efficiency at low loads and at loads equal to 20% -100% of the PSU's maximum-rated load.



Beating out most of its competitors, the PSU did pretty well with low loads. It also placed among the middle of the pack with normal loads by taking the lead from its XFX XTR-650 sibling, although it lost out to the Antec Edge 650 based on the same Seasonic platform.

Efficiency at Low Loads

In the next tests, we measured the efficiency of the Edison M-650 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.

Efficiency was pretty good at low loads, and the unit achieved close to 80% efficiency with only 40 W. The fan also spun a low speeds, which had it produce very little noise.

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 wasn't that efficient. In a Gold-certified PSU, we would like to see this rail crack the 80% mark in at least the last test.

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 values when the PSU is in standby mode (without any load on 5VSB).

No surprises here as the unit consumed significantly less than 0.5 W in standby.

Delta Temperature & Output Noise

We couldn't measure the fan's speed (RPMs) due to its white-colored fan blades that didn't reflect the laser beam of our tachometer properly, so we will only provide you with the delta difference between input and output temperature and the fan's output noise. The following results were obtained at 36°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.



Under normal conditions, the fan was very quiet with up to a load of 300-340 W, but it increased its speed afterward, and most of you would probably describe it annoyingly loud with anything above 400 W.