We made several tests with this power supply as described in the article Hardware Secrets Power Supply Test Methodology. All the tests described below were taken wit a room temperature between 46º and 50º C. During our tests the power supply temperature was between 49º and 52º C.
First we tested this power supply with five different loads patterns, trying to pull around 20%, 40%, 60%, 80% and 100% of its labeled maximum capacity (under “% Max Load” we list the actual percentage that was used), watching how the reviewed unit behaved under each load. On the table below we list the load patterns we used and the results for each load.
+12V2 is the second +12V input of our load tester and on this test it was connected to the power supply EPS12V connector.
Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
+12V1 | 5.5 A (66 W) | 12 A (144 W) | 18 A (216 W) | 25 A (300 W) | 30 A (360 W) |
+12V2 | 5.5 A (66 W) | 11 A (132 W) | 17 A (204 W) | 22 A (264 W) | 29 A (348 W) |
+5V | 2 A (10 W) | 4 A (20 W) | 6 A (30 W) | 8 A (40 W) | 8 A (40 W) |
+3.3 V | 2 A (6.6 W) | 4 A (13.2 W) | 6 A (19.8 W) | 8 A (26.4 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) | 0.8 A (9.6 W) |
Total | 160 W | 320 W | 483 W | 646 W | 799 W |
% Max Load | 19.9% | 40.0% | 60.0% | 80.8% | 100.0% |
Result | Pass | Pass | Pass | Pass | Pass |
Voltage Stability | Pass | Pass | Pass | Pass | Pass |
Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
AC Power | 188 W | 375 W | 580 W | 801 W | 1,038 W |
Efficiency | 85.1% | 85.3% | 83.3% | 80.6% | 77.0% |
We were satisfied with these results. BFG 800 W could deliver its labeled power under between 45º and 50º C and could maintain a high efficiency on tests 1 (20% load), 2 (40% load) and 3 (60% load). On test 4 (80% load) efficiency dropped to 80.6% but that is still good. The problem was when delivering its full 800 W, when efficiency dropped below 80% to 77%. This is why BFG isn’t advertising this power supply’s efficiency.
We were really impressed by the very low level of electrical noise produced by this power supply on its +12 V output, the lowest we’ve seen to date. On test 1 (20% load) we’ve seen only 15 mV of noise at the +12 V line, increasing to the 20 mV range for tests 2, 3 and 4 and reaching a maximum of 36.2 mV with the power delivering its full power. This is far below the 120 mV limit and we are talking about a power supply with a noise level 3.5 times below the limit, which is really outstanding. On the other hand with the power supply delivering 800 W noise level at +5 V line was of 27 mV and at +3.3 V line was of 25.4 mV. Even though these numbers are below the 50 mV limit for these lines, we expected something lower here, around 15 to 20 mV, especially when we have such a good filtering on the +12 V line. All these numbers are peak-to-peak figures. Below we show the noise level we found on the power supply outputs while the unit was operating at its full load (test number five).
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Figure 15: Noise level at +12V1 input of the load tester.
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Figure 16: Noise level at +12V2 input of the load tester.
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Figure 17: Noise level at +5V input of the load tester.
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Figure 18: Noise level at +3.3V input of the load tester.
The stability of the outputs was also great. All voltages were within 3% their nominal voltage, except the +5VSB on test 1, which was delivering 5.19 V (3.8% above the nominal voltage) and the +5 V on test 1, 2 and 5, which was delivering 5.17 V (3.4% above the nominal voltage). These values are great as they are below the 5% maximum tolerance (on our methodology we use 3% as our goal, which is a tighter figure).
