Akasa Essential Power 300 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 our tests, the +12VA and +12VB input were connected to the power supply single +12 V rail (the ATX12V connector was installed on the +12VB input of our load tester).
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12VA | 2 A (24 W) | 4 A (48 W) | 6 A (72 W) | 7.5 A (90 W) | 9.25 A (111 W) |
| +12VB | 1.5 A (18 W) | 3.75 A (45 W) | 5.5 A (66 W) | 7 A (84 W) | 9 A (108 W) |
| +5V | 1 A (5 W)< /td> | 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 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 | 62.1 W | 122.3 W | 184.6 W | 240.1 W | 303.7 W |
| % Max Load | 20.7% | 40.8% | 61.5% | 80.0% | 101.2% |
| Room Temp. | 44.0° C | 43.1° C | 44.6° C | 44.8° C | 45.7° C |
| PSU Temp. | 47.9° C | 46.9° C | 46.4° C | 46.6° C | 48.5° C |
| Voltage Regulation | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
| AC Power | 75.3 W | 143.2 W | 216.1 W | 284.5 W | 366.8 W |
| Efficiency | 82.5% | 85.4% | 85.4% | 84.4% | 82.8% |
| AC Voltage | 114.6 V | 113.9 V | 113.6 V | 113.0 V | 112.2 V |
| Final Result | Pass | Pass | Pass | Pass | Pass |
The Akasa Essential Power 300 W passed our tests with flying colors, being able to deliver its labeled wattage at high temperatures.
Efficiency was excellent, between 82.8% and 85.4%. This is outstanding for an entry-level power supply. In fact, the manufacturer could have got the 80 Plus Bronze certification with this unit (it has the standard 80 Plus certification).
Voltage regulation was superb, with all voltages within 3% of their nominal values, including the -12 V output. The ATX12V specification allows voltages to be up to 5% from their nominal values (10% for the -12 V output). Therefore this power supply presents all voltages closer to their nominal values than necessary all the time.
Noise and ripple levels were very low. Below you can see the results for the power supply outputs during test number five. The maximum allowed is 120 mV for the +12 V and -12 V outputs, and 50 mV for the +5 V, +3.3 V, and +5VSB outputs. All values are peak-to-peak figures.
Figure 17: +12VA input from load tester during test five at 303.7 W (34.6 mV)
Figure 18: +12VB input from load tester during test five at 303.7 W (37.6 mV)
Figure 19: +5V rail during test five at 303.7 W (18.2 mV)
Figure 20: +3.3 V rail during test five at 303.7 W (14.8 mV)
Let’s see how much more power we could pull from this unit.