Cooler Master Silent Pro Gold 800 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 both inputs were connected to the power supply single rail (+12VB input was connected to the power supply EPS12V connector and all other cables were connected to the load tester +12VA input).
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12VA | 5.5 A (66 W) | 12 A (144 W) | 18.5 A (222 W) | 23 A (276 W) | 29 A (348 W) |
| +12VB | 5.5 A (66 W) | 11 A (132 W) | 16 A (192 W) | 23 A (276 W) | 29 A (348 W) |
| +5V | 2 A (10 W) | 4 A (20 W) | 6 A (30 W) | 8 A (40 W) | 10 A (50 W) |
| +3.3 V | 2 A (6.6 W) | 4 A (13.2 W) | 6 A (30 W) | 8 A (26.4 W) | 10 A (33 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 | 163.2 W | 329.4 W | 488.8 W | 646.4 W | 802.4 W |
| % Max Load | 20.4% | 41.2% | 61.1% | 80.8% | 100.3% |
| Room Temp. | 45.9° C | 45.8° C | 44.2° C | 46.3° C | 44.5° C |
| PSU Temp. | 40.3° C | 41.0° C | 41.0° C | 41.9° C | 45.6° C |
| Voltage Regulation | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Fail on -12 V | Fail on -12 V | Pass | Fail on -12 V |
| AC Power | 186.6 W | 366.8 W | 554.8 W | 729.0 W | 931.4 W |
| Efficiency | 87.5% | 89.8% | 88.1% | 88.7% | 86.1% |
| AC Voltage | 113.4 V | 111.5 V | 110.4 V | 108.5 V | 104.7 V |
| Power Factor | 0.961 | 0.983 | 0.988 | 0.988 | 0.992 |
| Final Result | Pass | Pass | Pass | Pass | Pass |
Cooler Master Silent Pro Gold 800 W can really deliver its labeled wattage at high temperatures.
Being an 80 Plus Gold power supply, the manufacturer promises a 90% efficiency under typical load (i.e., 50% load or 400 W) and 87% efficiency at light (20% load, i.e., 160 W) and full (800 W) loads. In our tests efficiency at full load was at 86.1% – as we have been exhaustively explaining in our reviews, Ecos Consulting, the company behind 80 Plus, tests power supplies at 23° C, while we test them between 45° C and 50° C, and efficiency drops with temperature. Therefore our tests are more rigorous (and more realistic) than those conducted in order to get the 80 Plus certification (click here to learn more).
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 was always higher than we’d like to see in a supposedly high-end product. As you can see below, with the unit delivering 800 W, noise level at +12 V was around 95 mV. While still below the maximum allowed (120 mV), we always prefer to see power supplies presenting a noise level below half of the limit. The -12 V output failed to stay within proper range. During test one it was presenting a noise level of 108.2 mV, increasing to 120.6 mV on test two, 137.2 mV on test three, 119.2 mV on test four and 164.4 mV on test five. While this output is not as important as the others and is mainly used by some audio cards, we have to point out this flaw.
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.
< img class="aligncenter size-full wp-image-614" src="https://hardwaresecrets.com/wp-content/uploads/CM_SilentPro800w_12v11.gif" alt="Cooler Master Silent Pro Gold 800 W power supply" width="545" height="473" />Figure 19: +12VA input from load tester during test five at 802.4 W (95.2 mV).
Figure 20: +12VB input from load tester during test five at 802.4 W (96.6 mV).
Figure 21: +5V rail during test five at 802.4 W (17.8 mV).
Figure 22: +3.3 V rail during test five at 802.4 W (16.5 mV).
Let’s see if we can pull even more from Cooler Master Silent Pro Gold 800 W.