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 MK3S600 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 MK3S600. 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 until 60% load is high for a plain Bronze unit and like the most PSUs we have seen so far it peaks with 40% load (87.5%). Voltage regulation at +12V is tight enough and under 2%, at 5V it's looser but still below 3% and at 3.3V the deviation is high since it exceeds 4.4%. The claim that this unit can deliver its full power even at 50°C ambient is absolutely true since we conducted the full load test at 50.4°C and the PSU worked flawlessly. Finally at low-middle loads even at high ambient the fan is almost inaudible but at higher loads it makes its presence well felt. The good thing is that it outputs a low frequency hum so it's not annoying however it's loud enough.

Efficiency at Low Loads

In the next tests, we measure the efficiency of MK3S600 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.


Strangely enough, efficiency at low loads is pretty good, especially if we take into account the low 80 PLUS certification the unit carries. Even with 60W of load it's real close to the 80% mark and with 80W and 100W it easily surpasses it. This PSU will be a good choice if you operate your system at low loads for long periods.

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.


The 5VSB rail registers decent efficiency since it easily surpasses the equivalent ATX spec thresholds for each load level. However we want to see units surpassing 80% efficiency at this rail in #3 and #4 tests and this unit didn't manage to accomplish this. Unfortunately till now very few units managed to register over 80% efficiency at 5VSB.

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).


Phantom power is very low so the PSU is easily ErP Lot 6 2010 compliant.