OCZ ModXStream Pro 600 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.
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 +12V2 rails, while the +12VB input was connected to the power supply +12V1 rail (EPS12V connector).
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12VA | 4 A (48 W) | 9 A (108 W) | 13 A (156 W) | 17.5 A (210 W) | 21.5 A (258 W) |
| +12VB | 4 A (48 W) | 9 A (108 W) | 13 A (156 W) | 17.5 A (210 W) | 21.5 A (258 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 (5 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) | 0.5 A (6 W) |
| Total | 116.3 W | 244.8 W | 359.3 W | 484.1 W | 600.4 W |
| % Max Load | 19.4% | 40.8% | 59.9% | 80.7% | 100.1% |
| Room Temp. | 48.4° C | 47.5° C | 46.8° C | 45.6° C | 42.5° C |
| PSU Temp. | 45.3° C | 46.0° C | 46.7° C | 47.6° C | 42.4° C |
| Voltage Regulation | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
| AC Power | 136.6 W | 282.8 W | 420.7 W | 579.6 W | 733.0 W |
| Efficiency | 85.1% | 86.6% | 85.4% | 83.5% | 81.9% |
| AC Voltage | 114.9 V | 113.4 V | 112.3 V | 110.5 V | 109.5 V |
| Power Factor | 0.977 | 0.99 | 0.994 | 0.996 | 0.998 |
| Final Result | Pass | Pass | Pass | Pass | Pass |
OCZ ModXStream Pro 600 W can really deliver its labeled power, however during test five it shut down twice.
We were actually surprised with its performance. Since it has “only” the standard 80 Plus certification, we were expecting to see a unit with 80-82% efficiency across the board, but we are happy to be wrong: OCZ ModXStream Pro 600 W could achieve a high efficiency between 83.5% and 86.6% when we pulled up to 480 W. At full load (600 W) efficiency was at 81.9%, which is great – in fact these results are almost enough for this unit to get the 80 Plus Bronze certification.
Voltage regulation was outstanding, with all voltages within 3% from their nominal values – i.e., values closer to their “face value” than required, as the ATX12V specification allows voltages to be within 5% from their nominal values (10% for -12 V).
And then we have noise and ripple, which were below the maximum allowed (during test five -12 V output touched the 120 mV limit and +12 V was a little higher than we’d like to see, but still within specs). Below you can see the results during test five. The maximum allowed is 120 mV on +12 V and 50 mV on +5 V and +3.3 V. All these numbers are peak-to-peak figures.
Figure 16: +12VA input from load tester at 600.4 W (80.2 mV).
Figure 17: +12VB input from load tester at 600.4 W (80.6 mV).
Figure 18: +5 V rail with power supply delivering 600.4 W (30.2 mV).
Figure 19: +3.3 V rail with power supply delivering 600.4 W (18.8 mV).
Unfortunately we couldn’t pull any more power from this unit. If we tried to increase one amp on any output the unit would shut down.