Efficiency

Using the efficiency results from the previous page, we plotted a chart that shows the NJ520's efficiency at low loads and at loads equal to 20% -100% of the PSU's maximum-rated load.



The NJ520 managed to take the lead away from Seasonic's unit at light loads, and only fell behind the unit a bit with normal loads. Overall, it achieved very high efficiency with both light and normal loads.

Efficiency at Low Loads

In the next tests, we measured the NJ520'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 a capacity over 500 W). This is important for settings where the PC is in idle mode with Power Saving turned on.

This platform is incredibly efficient with low loads. As for the 80% mark – it was easily met with only 40 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 not only registered tight voltage regulation as its efficiency was also good. It even managed to score more than 80% in 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 when the PSU is in standby mode (without any load at 5VSB).

The NJ520 hardly consumes any power at all in standby.

Delta Temperature

Since this is a passive PSU, there will only be one graph instead of the three we normally reserve for PSUs with active cooling. The graph below shows the delta difference between input and output temperature. The results were obtained at 38°C-45°C ambient.



As you can see by the large Delta differences we recorded, its casing with a bunch of punched out holes does an excellent job of letting the hot air escape.