Test Setup

All measurements are performed utilizing ten electronic loads (seven Array 3711A, 300W each, and three Array 3710A, 150W each), which are able to deliver over 2500W of load and are controlled by a custom made software. We also use a Picoscope 3424 oscilloscope, a CHY 502 thermometer, a Fluke 175 multimeter and an Instek GPM-8212 power meter. Furthermore, in our setup we have included a wooden box, which along with a heating element is used as a Hot Box. Finally, we have at our disposal four more oscilloscopes (Rigol 1052E and VS5042, Stingray DS1M12 and a second Picoscope 3424) and a CEM DT-8852 sound level meter. In this article you will find more details about our equipment and the review methodology we follow. Finally, if the manufacturer states that the maximum operating temperature of the test unit is only 40°C then we try to stay near this temperature, otherwise we crank up the heat inside the hotbox up to 45-50°C.

Voltage Regulation Charts

The following charts show the voltage values of the main rails, recorded over a range from 60W to the maximum specified load, and the deviation (in percent) for the same load range.

5VSB Regulation Chart

The following chart shows how the 5VSB rail deals with the load we throw at it.

Efficiency Chart

In this chart you will find the efficiency of SF-500P14PE at low loads and at loads equal to 20-100% of PSU’s maximum rated load.

Voltage Regulation and Efficiency Measurements

The first set of tests reveals the stability of voltage rails and the efficiency of SF-500P14PE. The applied load equals to (approximately) 20%, 40%, 50%, 60%, 80% and 100%, of the maximum load that the PSU can handle. In addition, we conduct two more tests. In the first we stress the two minor rails (5V & 3.3V) with a high load, while the load at +12V is only 2A and in the second test we dial the maximum load that +12V can handle while load at minor rails is minimal.


Super Flower products don't stop amazing us with their ultra-high efficiency levels. This unit scored a 93% reading with 40% load and in six out of the eight tests efficiency is over 91%! Even at CL1 test where most of the efficient PSUs struggle to reach 80%, this one achieved nearly 87% efficiency! All testing was done at ultra high ambient temperatures, even then the fan didn't start till we reached the 80% of max rated capacity load test. Even while the fan was working at full RPMs output noise was kept at minimal levels, so in our humble opinion it is better to prefer the normal fan operation to keep the internal temperature low at all cases, leading to increased lifespan for almost all of its electronic components.
Voltage regulation at +12V is very tight while on the minor rails varies from decent (5V) to somewhat loose (3.3V). Also at 5VSB voltage regulation is nothing to write home about, only that it is loose. Finally, as you can see from the table above that the PSU had no problem at all delivering its full continuous power at nearly 50°C operating temperatures. Here we should note that the unit features a very cool operation, thanks to its ultra-high efficiency, so we had to try hard to increase the temperature inside the hotbox.

Efficiency at Low Loads

In the next tests, we measure the efficiency of SF-500P14PE at loads much lower than 20% of its maximum rated load (the lowest load that the 80 Plus Standard measures). The loads that we dial are 40, 60, 80 and 100W (for PSUs with over 500W capacity). This is important for scenarios in which a typical office PC is in idle with power saving turned on.


At low loads efficiency is outstanding! With only 40W load it reaches an out of this world 85.11% reading! This time we skipped the 100W test since we already conducted it in the previous series of tests. With 80W load the PSU exceeded 90% efficiency. This unit, along with the Kingwin AP-550 (which is also made by Super Flower and is based on the same platform) are the new efficiency kings at these tests.

5VSB Efficiency

ATX spec states that the 5VSB standby supply's efficiency should be as high as possible and recommends 50% or higher efficiency with 100mA load, 60% or higher with 250mA load and 70% or higher with 1A or more load.
We will take four measurements, three at 100 / 250 / 1000 mA and one with the full load that 5VSB rail can handle.


On the 5VSB rail efficiency is not so great, at least compared to the total efficiency of the unit, but it is decent without any doubt. What we didn't like so much is the loose voltage regulation here, something however that won't affect most of the devices fed by this rail. Here we should state that the voltage regulation graph shown on the start of the page does not derive solely from the data of the table above, but mainly from the data found on the tables preceding this one.

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 (On but without any load at its rails) and the power consumption when the PSU is in standby (without any load at 5VSB).


As we are used to see in almost every modern PSU, vampire power is low and easily meets the ErP Lot 6 2010 requirements. The use of dedicated standby PWM controllers significantly reduces energy consumption in standby, saving the environment and your wallet at the same time.