Kingwin ABT-450MM 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. All the tests described below were taken with a room temperature between 44.8° C and 50° C. During our tests the power supply temperature was between 50° C and 56° C.
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.
On this review we added a sixth pattern, also pulling 100% of the power supply load (450 W) but with a different current configuration. On test number five we respected the limit posted on the power supply label for the combined +12 V power, which is of 336 W. To respect this limit we had to keep the +12 V currents lower than what we wanted and increase the currents on +5 V and +3.3 V outputs. On test number six we didn’t respect the +12 V combined power limit for this power supply and test it as we wanted, pulling more current from +12 V outputs and less from +5 V and +3.3 V outputs, as this configuration reflects better a typical usage from 2008. Under this scenario we were pulling a total of 384 W from the +12 V outputs.
We also wanted to do these tests because we were criticized for not respecting the +12 V combined limit in our Huntkey Green Star 450 W review, some claiming that maybe this was the reason this Huntkey power supply exploded when we tried to pull 450 W from it. So in this present review we will test the power supply under two different scenarios for its 100% load to see what happens.
+12V2 is the second +12V input of our load tester and on this test it was connected to the power supply ATX12V connector.
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.
| Input | Test 1 | Test 2 | Test 3 | Test 4 | < strong>Test 5 | Test 6 |
| +12V1 | 3 A (36 W) | 6.5 A (78 W) | 10 A (120 W) | 13 A (156 W) | 14 A (168 W) | 17 A (204 W) |
| +12V2 | 3 A (36 W) | 6.5 A (78 W) | 9 A (108 W) | 12.5 A (150 W) | 14 A (168 W) | 15 A (180 W) |
| +5V | 1 A (5 W) | 2 A (10 W) | 4 A (20 W) | 5 A (25 W) | 12 A (60 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) | 12 A (39.6 W) | 6 A (19.8 W) |
| +5VSB | 1 A (5 W) | 1 A (5 W) | 1 A (5 W) | 1.5 A (7.5 W) | 2 A (10 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) | 0.6 A (7.2 W) | 0.5 A (6 W) |
| Total | 91.2 W | 183.3 W | 271.2 W | 358.9 W | 449.5 W | 445 W |
| % Max Load | 20.3% | 40.7% | 60.3% | 79.8% | 99.9% | 98.9% |
| Result | Pass | Pass | Pass | Pass | Pass | Pass |
| Voltage Stability | Pass | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass | Pass |
| AC Power | 115 W | 224 W | 336 W | 454 W | 595 W | 584 W |
| Efficiency | 79.3% | 81.8% | 80.7% | 79.1% | 75.5% | 76.2% |
Obsolete design or not this power supply could truly deliver its labeled power at 50° C. Also, it survived to both our scenarios for the 100% load tests: respecting the maximum combined +12 V wattage stated on the power supply label or not.
Efficiency could be better, but reached a somewhat good result for a power supply based on an old design, capable of surpassing 80% on tests number two (40% load) and three (60%). So if you use this power supply with a simple system pulling between 180 W and 270 W you will have a very good efficiency.
Voltage regulation was also great, within 3% of the nominal voltages, except -12 V output, that was at -11.20 V at test one, -11.55 V at test two, and -12.45 V at tests five and six. Even though according to ATX specification -12 V line can vary 10% of its nominal voltage, we wanted to see a value closer to -12 V here.
The highlight of this power supply was electrical noise and ripple, which was at a very low level. When pulling the full 450 W from this power supply noise at +12V1 was 24.6 mV, at +12V2 was 29.8 mV, at +5 V was 20.8 mV and at +3.3 V was 23.6 mV (values for pattern number five). Just to remember, maximum admissible values are 120 mV for +12 V and 50 mV for +5 V and +3.3 V. This power supply had more ripple than noise (ripple is an oscillation on the output waveform, while noise are the spikes present on that oscillation; all other power supplies we’ve seen to date had more noise than ripple – compare the images below with images obtained on other power supplies to see the difference), but this doesn’t change the fact that it was below maximum specs.
Figure 12: Noise and ripple at +12V1 input from our load tester.
Figure 13: Noise and ripple at +12V2 input from our load tester.
Figure 14: Noise and ripple at +5V input from our load tester.
Figure 15: Noise and ripple at +3.3V input from our load tester.