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-1000P 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-1000P. 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.


Efficiency on this unit is really high. Seven out of the eight tests, on the above table, are over 90% and three of them are over 92%. If this isn't impressive then what else could be. Voltage regulation at +12V is pretty tight while on the minor rails it loosens a bit, although not too much. In general the direct competitor of this unit, the mighty Seasonic P1000 registers a little tighter voltage regulation at +12V, much tighter on the minor rails and marginally higher efficiency at 20-100% load range. Nevertheless the Seasonic competitor costs much more and is really noisy at high loads/ambient. On the contrary the Super Flower unit is really quiet since it was operating in fanless mode up to 50% load test and even when the fan engaged it was practically inaudible. During CrossLoad #2 test, with over 50°C ambient, the only way to check if the fan was spinning was to take a look at it, since it output minimal noise. This PSU will be highly appreciated, that's for sure, by all noise haters out there.

Efficiency at Low Loads

In the next tests, we measure the efficiency of SF-1000P 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 the SF-1000P registers some of the highest efficiency numbers we have ever seen at such low loads. This unit is simply impressive since, although it has 1000W capacity, even with only 40W load it manages to achieve 76.5% efficiency and with 20W more load it easily passes the 80% mark.

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.


At test#1 efficiency starts low, failing to pass the threshold that the ATX spec recommends but at the reamining tests it is constantly above the corresponding limits. By the way, voltage regulation at 5VSB is really good, although we would prefer a little more power at the expense of tight voltage regulation.

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).


No surprises here. The unit easily meets the ErP Lot 6 2010 requirements. Lately almost all manufacturers comply with this directive, since it is essential for all products sold in the EU.