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 EA-650 Platinum 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 EA-650 Platinum. 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 is high overall but is lower than the Platinum requirements, even though we test with 230VAC power input where efficiency usually is 1-1.5% higher than with 115VAC, the power input that 80 Plus organization uses to certify desktop PSUs. This made us wonder so we decided to run some extra tests with 115VAC input this time. As you can see from the efficiency chart above, indeed with loads up to about 250W at 115VAC, efficiency is higher than at 230VAC. Only at higher loads 230VAC takes the lead.
Only 5V regulation is tight enough for our standards, while the +12V and 3.3V rails registered larger deviations. As it seems the pursuit of the highest possible efficiency showed its negative effects on the +12V rail which is close to 3% voltage regulation. Surely that's still far from the 5% limit but in comparison to other similar capacity units we have tested in the past, it doesn't look so good. Regarding output noise, even at full load and nearly 48°C ambient it was fairly quiet. Also the small difference between the PSU's input/output temperature is mainly due to the small heatsinks in the internal of the unit and on top of that indicates that the fan is working at low RPMs, so it doesn't make much noise.

Efficiency at Low Loads

In the next tests, we measure the efficiency of EA-650 Platinum 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 these tests efficiency is pretty satisfactory since at two out of the four tests it easily surpasses the 80% mark. Even with only 40W of load efficiency remains over 70% and with a mere 20W more it gets an impressive 7.5% boost. This unit will totally satisfy the users that also need good efficiency at bottom low loads.

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 was a pleasant surprise since efficiency here is pretty high in all tests. If at test#4 the unit scored over 80% then we would be left completely satisfied but apparently you can't have it all in this world.

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).


In standby mode the PSU draws very little power from the grid. With only 0.18W vampire power is one of the most economic units we have ever tested, in standby mode of course.