Rosewill Performance 650 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. On the “Total” row we are using the real amount of power being delivered, as measured by our load tester.
+12V1 and +12V2 are the two independent +12V inputs from our load tester and during out tests the +12V1 input was connected to the power supply +12V1 (video card auxiliary power connector) and +12V4 (main motherboard cable and peripheral power connectors) rails, while the +12V2 input was connected to the power supply +12V3 rail (EPS12V connector).
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12V1 | 5 A (60 W) | 10 A (120 W) | 14 A (168 W) | 19 A (228 W) | 26.5 A (318 W) |
| +12V2 | 4.5 A (54 W) | 10 A (120 W) | 14 A (168 W) | 19 A (228 W) | 22 A (264 W) |
| +5V | 1 A (5 W) | 2 A (10 W) | 4 A (20 W) | 5 A (25 W) | 6 A (30 W) |
| +3.3 V | 1 A (3.3 W) | 2 A (6.6 W) | 4 A (13.2 W) | 5 A (16.5 W) | 6 A (19.8 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 | 134.4 W | 269.7 W | 385.8 W | 515.0 W | 648.8 W |
| % Max Load | 20.7% | 41.5% | 59.4% | 79.2% | 99.8% |
| Room Temp. | 47.3° C | 47.1° C | 47.3° C | 50.1° C | 47.8° C |
| PSU Temp. | 50.6° C | 50.2° C | 50.2° C | 51.9° C | 53.4° C |
| Voltage Stability | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Fail on +5VSB |
| AC Power | 153 W | 305 W | 441 W | 601 W | 789 W |
| Efficiency | 87.8% | 88.4% | 87.5% | 85.7% | 82.2% |
| Final Result | Pass | Pass | Pass | Pass | Fail |
The highlight from this power supply was clearly its efficiency, which was amazingly high, especially because the manufacturer says this power supply has a minimum efficiency of 79%. When we pulled up to 60% of the labeled power (up to 390%) efficiency was between 87.5% and 88.4%. When we pulled 80% of the labeled power (520 W) efficiency was still high, at 85.7%. Only at 100% load (650 W) efficiency dropped, but still above the 80% mark.
There were some problems with this power supply though. When working at 80% load noise level at +5VSB was too high (48 mV), too close to the 50 mV limit. At 100% load noise level at +5VSB was at 58 mV, above the maximum allowed. At full load noise level at +12V2 input from our load tester (which was connected to the unit’s +12V3 rail) was too high (98.6 mV), but still under the maximum allowed (120 mV). Ditto for -12 V (95 mV). All values are peak-to-peak.
And when pulling 650 W from this unit, it shut down after two minutes, when some protection kicked in (most probably the overload or over temperature protection). This seems to be a textbook example of a power supply labeled at 25° C, a temperature that is never reached inside the PC case (power supplies lose their ability to deliver current and thus power with temperature). We test power supplies at more realistic temperatures, between 45° C and 50° C.
Figure 13: Noise level at +12V1 with the reviewed power supply delivering 648.8 W (76.4 mV).
Figure 14: Noise level at +12V2 with the reviewed power supply delivering 648.8 W (98.6 mV).
Figure 15: Noise level at +5 V with the reviewed power supply delivering 648.8 W (32.2 mV).
Figure 16: Noise level at +3.3 V with the reviewed power supply delivering 648.8 W (39.8 mV).
Now let’s see if we can pull even more power from Performance 650 W.