Kingwin Mach 1 ABT-700MA1S 700 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. Then we tried to pull even more power from this unit and the results for this test are in the next page.
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.
+12V2 is the second +12V input from our load tester and during our tests we connected the power supply EPS12V connector to it. As explained, even though this power supply is listed as having four +12 V rails this information isn’t correct, as it uses a single-rail design.
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12V1 | 5 A (60 W) | 10.5 A (126 W) | 15.5 A (186 W) | 20.5 A (246 W) | 25 A (300 W) |
| +12V2 | 5 A (60 W) | 10.5 A (126 W) | 15.5 A (186 W) | 20.5 A (246 W) | 25 A (300 W) |
| +5V | 1 A (5 W) | 2 A (10 W) | 4 A (20 W) | 6 A (30 W) | 10 A (50 W) |
| +3.3 V | 1 A (3.3 W) | 2 A (6.6 W) | 4 A (13.2 W) | 6 A (19.8 W) | 10 A (33 W) |
| +5VSB | 1 A (5 W) | 1.5 A (7.5 W) | 2 A (10 W) | 2 A (10 W) | 2.2 A (11 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 | 140.1 W | 279.6 W | 416.8 W | 550.8 W | 686.9 W |
| % Max Load | 20.0% | 39.9% | 59.5% | 78.7% | 98.1% |
| Room Temp. | 45.3° C | 46.1° C | 47.5° C | 46.0° C | 50.3° C |
| PSU Temp. | 49.0° C | 48.7° C | 50.2° C | 49.7° C | 55.4° C |
| Voltage Stability | Fail on -12 V | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
| AC Power | 170 W | 333 W | 505 W | 702 W | 932 W |
| Efficiency | 82.4% | 84.0% | 82.5% | 78.5% | 73.7% |
| Final Result | Pass | Pass | Pass | Pass | Pass |
This power supply could not only deliver its labeled power at 50° C, but more than that (see results in the next page).
The -12 V output, however, was out of spec when we pulled 20% of the power supply nominal capacity (140 W), reading -10.74 V while the maximum allowed for this output is -10.80 V. On tests one and two +5 V output was with a voltage a little higher than we’d like to see, but still within the 5% limit set by the ATX specification.
On the other hand ripple and noise levels were very low, far below the maximum allowed. Below you can see the results achieved for test 5. Noise level at +3.3 V and +5 V was lower than half the maximum allowed (50 mV peak-to-peak) and noise level at +12 V was less than a third of the maximum allowed (120 mV peak-to-peak).
The bad news about this power supply is its efficiency. It can only stay above 80% efficiency if you pull up to 60% of its nominal capacity (420 W). If you pull around 80% of its capacity you will see efficiency dropping below the 80% mark, with it sinking to around 74% when you pull the full 700 W from the reviewed unit.
Figure 18: Noise level at +12V1 input from our load tester with the reviewed unit delivering 700 W (37.8 mV).
Figure 19: Noise level at +5 V input from our load tester with the reviewed unit delivering 700 W (31 mV).
Figure 20: Noise level at +3.3 V input from our load tester with the reviewed unit delivering 700 W (22.2 mV).
Now let’s see how much power we could pull from this unit keeping it working inside ATX specs.