Efficiency

Using the efficiency results from the previous page, we plotted a chart showing efficiency of the Power Zone 1000 W at low loads and at loads equal to 20%-110% of the PSU's maximum-rated load.



The unit manages to pass ahead of several Gold and Platinum PSUs at low loads, which is very impressive. It, however, only takes last place with normal loads since we compared it to Gold and Platinum units with 1 kW capacity, though it still scores an above 90% overall reading, which only places it a bit behind the competition in its price range.

Efficiency at Low Loads

In the next tests, we measured the efficiency of the Power Zone 1000 W 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 of over 500 W). This is important for settings where the PC is in idle mode with Power Saving turned on.

The ACRF topology does wonders in terms efficiency at low loads, and the Power Zone 1000 W managed to easily crack the 80% mark in three out of the four tests we ran.

5VSB Efficiency

The ATX spec 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.

5VSB efficiency is nothing to write home about, and it, to make things even worse, even dropped very low, close to 70%, during the full load test, which clearly shows that the 3 A are on the verge of what is possible for the circuit generating this rail.

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).

Phantom power was kept at very low levels.

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 the fan's noise from 1 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 30 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 entire operating range of the PSU. The same conditions of the above graph apply to our measurements, but the ambient in this case was between 28°C and 30°C.



The cooling fan can be characterized as fairly quiet at up to about half the maximum power this PSU can deliver, but its output noise increases to the point of being annoying at full load.