Athena Power AP-MFATX35 350 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 input was connected to the power supply +12V1 rail, while the +12VB input was connected to the power supply +12V2 rail (EPS12V connector).
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12VA | 2 A (24 W) | 4.5 A (54 W) | 7 A (84 W) | 9 A (108 W) | 11.25 A (135 W) |
| +12VB | 2 A (24 W) | 4.5 A (54 W) | 7 A (84 W) | 9 A (108 W) | 11 A (132 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) | 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 A (5 W) | 1.5 A (7.5 W) | 2 A (10 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 | 66.2 W | 133.3 W | 208.8 W | 274.8 W | 348.4 W |
| % Max Load | 18.9% | 38.1% | 59.7% | 78.5% | 99.5% |
| Room Temp. | 42.4° C | 41.8° C | 41.7° C | 44.1° C | 45.9° C |
| PSU Temp. | 47.7° C | 50.7° C | 50.5° C | 51.3° C | 54.4° C |
| Voltage Stability | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Fail at +3.3 V |
| AC Power | 83.1 W | 158.8 W | 248.8 W | 331.6 W | 428.8 W |
| Efficiency | 79.7% | 83.9% | 83.9% | 82.9% | 81.3% |
| AC Voltage | 117.4 V | 117.3 V | 116.2 V | 115.7 V | 114.7 V |
| Power Factor | 0.947 | 0.972 | 0.984 | 0.989 | 0.991 |
| Final Result | Pass | Pass | Pass | Pass | Fail |
The Athena Power AP-MFATX35 can really deliver its labeled wattage.
Efficiency was above 82% only when we pulled between 40% and 80% of the unit’s labeled wattage (i.e., between 140 W and 280 W). At light (20%, i.e., 70 W) load, efficiency was a little below 80%. As we always point out, Ecos Consulting, the company behind the 80 Plus certification, tests power supplies at only 23° C, while we test them at higher (and more realistic) temperatures. It is common to see units that passed the 80 Plus certification that wouldn’t pass if Ecos Consulting were using our testing methodology.
Voltage regulation was acceptable, with all voltages within the proper range. The ATX12V specification says that positive voltages must be within 5% of their nominal values and negative voltages must be within 10% of their nominal values.
Noise and ripple levels were really high with the unit delivering 350 W, with the +3.3 V output presenting a noise level above the maximum allowed. Below you can see the results for the power supply outputs during test number five. The maximum allowed is 120 mV for +12 V and -12 V outputs, and 50 mV for +5 V, +3.3 V and +5VSB outputs. All values are peak-to-peak figures.
Figure 19: +12VA input from load tester during test five at 348.4 W (98.8 mV)
Figure 20: +12VB input from load tester during test five at 348.4 W (95.2 mV)
Figure 21: +5 V rail during test five at 348.4 W (46.2 mV)
Figure 22: +3.3 V rail during test five at 348.4 W (54.6 mV)
Let’s see if we can pull more than 350 W from this unit.