Rosewill SilentNight 500 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 the behavior of the reviewed unit 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 powers listed for each test, you may find a different value than what is posted under “Total” below. Since each output can have a slight variation (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 and +12VB inputs were connected to the power supply’s single +12 V rail. (The +12VB input was connected to the power supply EPS12V connector.)
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12VA | 3.5 A (42 W) | 7.5 A (90 W) | 10.5 A (126 W) | 14 A (168 W) | 17.5 A (210 W) |
| +12VB | 3.5 A (42 W) | 7 A (84 W) | 10.5 A (126 W) | 14 A (168 W) | 17 A (204 W) |
| +5 V | 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) | 1.5 A (7.5 W) | 2 A (10 W) | 2.5 A (12.5 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 | 104.8 W | 210.5 W | 314.3 W | 425.9 W | 502.2 W |
| % Max Load | 21.0% | 42.1% | 62.9% | 85.2% | 100.4% |
| Room Temp. | 45.9° C | 45.2° C | 45.2° C | 45.6° C | 46.9° C |
| PSU Temp. | 52.7° C | 52.9° C | 53.4° C | 54.6° C | 56.2° C |
| Voltage Regulation | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
| AC Power | 114.8 W | 227.2 W | 341.4 W | 468.1 W | 556.8 W |
| Efficiency | 91.3% | 92.6% | 92.1% | 91.0% | 90.2% |
| AC Voltage | 118.0 V | 117.3 | 115.9 V | 114.8 V | 113.8 V |
| Power Factor | 0.984 | 0.983 | 0.986 | 0.989 | 0.991 |
| Final Result | Pass | Pass | Pass | Pass | Pass |
We were really impressed by the efficiency results of the Rosewill SilentNight 500 W, always above 90% at high temperatures.
Voltage regulation was also outstanding, with all voltages within 3% of their nominal values. The ATX12V specification states that positive voltages must be within 5% of their nominal values, and negative voltages must be within 10% of their nominal values.
Let’s discuss the ripple and noise levels on the next page.