Load Tests
Contents
We conducted several tests with this power supply, as described in the article Hardware Secrets Power Supply Test Methodology. All the tests described below were taken with a room temperature between 45° and 47° C. During our tests the power supply temperature was between 47° and 48° C.
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.
+12V2 is the second +12V input of our load tester and on this test it was connected to the power supply EPS12V connector. Keep in mind that power supply uses a single rail design.
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12V1 | 4.5 A (54 W) | 8.5 A (102 W) | 16 A (192 W) | 25 A (300 W) | 33 A (396 W) |
| +12V2 | 4.5 A (54 W) | 8.5 A (102 W) | 10 A (120 W) | 10 A (120 W) | 10 A (120 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) | 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) | 0.8 A (9.6 A) |
| Total | 128 W | 232 W | 359 W | 486 W | 607 W |
| % Max Load | 21% | 38% | 59% | 80% | 99.5% |
| Voltage Stability | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
| Efficiency (1) | 86.5% | 88.2% | 87.3% | 85.3% | 83.6% |
| AC Power (2) | 152.6 W | 271.8 W | 423.4 W | 584.6 W | 743.0 W |
| Efficiency (2) | 83.7% | 85.4% | 84.5% | 82.8% | 80.6% |
| AC Voltage | 115.4 V | 114.3 V | 112.9 V | 111.3 V | 109.5 V |
| Power Factor | 0.987 | 0.994 | 0.996 | 0.997 | 0.997 |
| Final Result | Pass | Pass | Pass | Pass | Pass |
Updated 07/03/2009: We re-tested this power supply using our new GWInsteak GPM-8212 power meter, which is a precision instrument and provides accuracy of 0.2% and thus presenting the correct readings for AC power and efficiency (results marked as "2" on the table above; results marked as "1" were measured with our previous power meter from Brand Electronics, which isn’t so precise as you can see). We also added the numbers for AC voltage during our tests, an important number as efficiency is directly proportional to AC voltage (the higher AC voltage is, the higher efficiency is). Also, manufacturers usually announce efficiency at 230 V, which usually inflates efficiency numbers. We added power factor (PF) numbers as well. These numbers measure the efficiency of the power supply active PFC circuit. This number should be as close to 1 as possible.
As you can see this power supply could not only deliver its labeled power at 45° C but could keep an high efficiency between 84.5% and 85.4% when delivering between 40% and 60% of this labeled capacity (between 244 W and 366 W). At light load (20% load, i.e., 122 W) efficiency was also high at 83.7%. At 80% load (488 W) efficiency dropped but was still at a somewhat high value (82.8%). At full load (610 W) efficiency dropped a lot, but still above the 80% mark.
As for noise, the maximum level we’ve seen was of 47 mV peak-to-peak on +12V1 input during test number four, which is well below the 120 mV maximum allowed.
After being happy with these results, we tried to pull even more power from Silencer 610 EPS12V but we couldn&r
squo;t: after increasing one amp at +12V1, +12V2, +5V or +3.3V the power supply wouldn’t turn on.
Then we started our next test, which was trying to figure out the maximum peak power this unit could handle. We started at load 1, then switched to load 2 and so on, after reaching load 5 we increased the current at +12V1, +12V2, +5V and +3.3V to the maximum possible with the power supply not shutting itself down and with the voltages and noise level within the proper working range. We came out with the following maximum peak specs for this unit:
| Input | Maximum Peak |
| +12V1 | 33 A (396 W) |
| +12V2 | 18 A (216 W) |
| +5V | 10 A (50 W) |
| +3.3 V | 10 A (33 W) |
| +5VSB | 3 A (15 W) |
| -12 V | 0.8 A (9.6 W) |
| Total | 708 W |
| % Max Load | 116.06% |
| Efficiency (1) | 82% |
| AC Power (2) | 897 W |
| Efficiency (2) | 78.9% |
| AC Voltage | 107.2 V |
| Power Factor | 0.997 |
The power supply, however, couldn’t work constantly at these specs, however, and that is why we are calling them “peak.” We made this test just to let you know how much is the maximum power you can draw from this power supply for very short periods of time. After some minutes noise starts increasing until the power supply shuts itself down. But this is an impressive result, as we are talking about a room temperature of 45° C.
Also all important protections worked as expected, as the power supply shut down automatically under over power and over current situations – cheap power supplies simply burn when stressed out due to the lack of such protections. The bottom line is: Silencer 610 EPS12V survived to our load tests, working just fine after them.
Also the power supply fan started spinning faster as the temperature increased. In fact this power supply uses a good name, “Silencer”: we could only hear the fan spinning under high load.
