Enermax REVOLUTION85+ 920 W Power Supply Review
Load Tests
Contents
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. In 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. During this test the +12VA input was connected to the power supply +12V1 and +12V4 rails, while the +12VB input was connected to the power supply +12V1 rail.
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12VA | 7 A (84 W) | 13 A (156 W) | 20 A (240 W) | 26 A (312 W) | 33 A (396 W) |
| +12VB | 6 A (72 W) | 12 A (144 W) | 19 A (228 W) | 26 A (312 W) | 33 A (396 W) |
| +5V | 2 A (10 W) | 6.5 A (32.5 W) | 8.5 A (42.5 W) | 11 A (55 W) | 13.5 A (67.5 W) |
| +3.3 V | 2 A (6.6 W) | 6 A (19.8 W) | 8 A (26.4 W) | 11 A (36.3 W) | 13.5 A (44.55 W) |
| +5VSB | 1 A (5 W) | 2 A (10 W) | 2 A (10 W) | 3 A (15 W) | 3 A (15 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 | 186.6 W | 367.8 W | 557.3 W | 738.1 W | 923.9 W |
| % Max Load | 20.3% | 40.0% | 60.6% | 80.2% | 100.4% |
| Room Temp. | 45.3° C | 43.6° C | 45.6° C | 47.5° C | 47.8° C |
| PSU Temp. | 39.4° C | 40.3° C | 40.8° C | 42.3° C | 46.0° C |
| Voltage Regulation | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
| AC Power | 206.4 W | 406.1 W | 626.0 W | 855.0 W | 1097.0 W |
| Efficiency | 90.4% | 90.6% | 89.0% | 86.3% | 84.2% |
| AC Voltage | 113.1 V | 110.7 V | 108.1 V | 104.8 V | 103.0 V |
| Power Factor | 0.978 | 0.991 | 0.995 | 0.997 | 0.998 |
| Final Result | Pass | Pass | Pass | Pass | Pass |
The Enermax REVOLUTION85+ 920 W can really deliver its labeled wattage at high temperatures.
Efficiency was at outstanding levels when we pulled up to 60% of the unit’s labeled load (i.e., up to 550 W), between 89% and 90%. Efficiency dropped to 86% at 80% load (736 W), and to 84% at full load (920 W). The 80 Plus Silver certification promises 85% minimum efficiency at 20% and 100% loads and 88% minimum efficiency at 50% load, but Ecos Consulting, the company behind 80 Plus, tests power supplies at a room temperature of only 23° C, which is unrealistic. We test power supplies at temperatures between 45° C and 50° C and that is why we usually see lower efficiency numbers compared to the 80 Plus certification, since efficiency drops with temperature.
Voltage regulation was very good, with all voltages within 3% of their nominal values (i.e., voltages closer to their “face value” than required by the ATX12V specification that allows a 5% tolerance for all positive voltages and 10% for -12 V). The exception was for the -12 V output, which was outside this tight regulation, but was still inside the proper range.
Noise and ripple were very low at all times. Below you can see the results for the power supply outputs during test number five. The maximums allowed are 120 mV for +12 V and -12 V, and 50 mV for +5 V and +3.3 V. All values are peak-to-peak figures.
Let’s see if we can pull even more from the Enermax REVOLUTION85+ 920 W.