We conducted several tests with this power supply, as described in the article Hardware Secrets Power Supply Test Methodology.
First we tested this power supply with five different load patterns, trying to pull around 20%, 40%, 60%, 80%, and 100% of its labeled maximum capacity (actual percentage used listed under “% Max Load”), watching how the reviewed unit behaved under each load. In the table below we list the load patterns we used and the results for each load.
If you add all the power listed for each test, you may find a different value than what is posted under “Total” below. Since each output can vary slightly (e.g., the +5 V output working at +5.10 V), the actual total amount of power being delivered is slightly different than the calculated value. On the “Total” row we are using the real amount of power being delivered, as measured by our load tester.
The +12VA and +12VB inputs listed below are the two +12 V independent inputs from our load tester. Since this power supply in reality has only one +12 V rail (see explanation in the previous page), both inputs were connected to the single rail present. The +12VB input was connected to the power supply EPS12V connector, while other connectors where installed on the +12VA input.
|Input||Test 1||Test 2||Test 3||Test 4||Test 5|
|+12VA||4 A (48 W)||7.5 A (90 W)||11 A (132 W)||14.5 A (174 W)||18 A (216 W)|
|+12VB||3.5 A (42 W)||7.5 A (90 W)||11 A (132 W)||14.5 A (174 W)||18 A (216 W)|
|+5V||1 A (5 W)||2 A (10 W)||4 A (20 W)||6 A (30 W)||8 A (40 W)|
|+3.3 V||1 A (3.3 W)||2 A (6.6 W)||4 A (13.2 W)||6 A (19.8 W)||8 A (26.4 W)|
|+5VSB||1 A (5 W)||1 A (5 W)||1.5 A (7.5 W)||2 A (10 W)||2.5 A (12.5 W)|
|-12 V||0.5 A (6 W)||0.5 A (6 W)||0.5 A (6 W)||0.5 A (6 W)||0.5 A (6 W)|
|Total||110.4 W||205.3 W||313.6 W||417.2 W||520.1 W|
|% Max Load||21.2%||39.5%||60.3%||80.2%||100.0%|
|Room Temp.||44.1° C||43.8° C||44.9° C||47.3° C||45.9° C|
|PSU Temp.||45.0° C||45.2° C||46.0° C||48.1° C||50.3° C|
|Ripple and Noise||Pass||Pass||Pass||Pass||Pass|
|AC Power||129.4 W||237.3 W||365.9 W||494.6 W||631.0 W|
|AC Voltage||114.2 V||113.2 V||111.8 V||110.5 V||108.9 V|
Seasonic S12II Bronze 520 W can really deliver its labeled wattage at high temperatures.
Efficiency was very high all the times, staying between 85.3% and 86.55% when we pulled up to 60% of the power supply labeled wattage (i.e., up to 312 W). At 80% load (416 W) efficiency was still high at 84.4%. And when delivering its full 520 W the reviewed unit achieved 82.4% efficiency. Therefore this unit can really maintain the 80 Plus Bronze minimum requirements under real-world temperatures. If you follow our reviews you know by now that not all 80 Plus-certified power supplies can deliver the efficiency that they promise because 80 Plus certification is done at a room temperature of only 23° C and efficiency drops with temperature.
Voltages regulation is another highlight from Seasonic S12II Bronze 520 W: all voltages were closer to their nominal voltages than required, staying within a 3% tolerance, while ATX12V specification allows a 5% tolerance. This includes the -12 V output.
And noise and ripple were amazingly low, as you can see below. The maximum allowed is 120 mV for the +12 V output and 50 mV for the +5 V and +3.3 V outputs. All numbers are peak-to-peak figures.
Let’s see if we can pull more than 520 W from this unit.