
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.
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.
The +12V1 and +12V2 inputs listed below are the two +12 V independent inputs from our load tester. During this test both were connected to the single +12 V rail from this power supply.
Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
+12V1 | 5 A (60 W) | 10 A (120 W) | 14.5 A (174 W) | 19 A (228 W) | 24 A (288 W) |
+12V2 | 4.5 A (54 W) | 9.5 A (114 W) | 14 A (168 W) | 19 A (228 W) | 24 A (288 W) |
+5V | 1 A (5 W) | 2 A (10 W) | 4 A (20 W) | 5 A (25 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) | 6 A (19.8 W) |
+5VSB | 1 A (5 W) | 1 A (5 W) | 1.5 A (7.5 W) | 2 A (10 W) | 2.5 A (12.5 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 | 134.8 W | 264.4 W | 390.3 W | 513.3 W | 632.4 W |
% Max Load | 21.4% | 42.0% | 62.0% | 81.5% | 100.4% |
Room Temp. | 46.1º C | 45.9º C | 47.2º C | 49.3º C | 49.2º C |
PSU Temp. | 47.0º C | 47.8º C | 48.9º C | 50.6º C | 52.3º C |
Voltage Regulation | Pass | Pass | Pass | Pass | Pass |
Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
AC Power | 159.8 W | 305.3 W | 453.1 W | 604.6 W | 760.4 W |
Efficiency | 84.4% | 86.6% | 86.1% | 84.9% | 83.2% |
AC Voltage | 113.3 V | 111.6 V | 110.3 V | 108.8 V | 108.8 V |
Power Factor | 0.970 | 0.990 | 0.995 | 0.997 | 0.997 |
Final Result | Pass | Pass | Pass | Pass | Pass |
Nexus RX-6300 can really deliver 630 W at practically 50º C.
Efficiency was high in all load patterns, staying above 86% when we pulled between 40% and 60% from its labeled capacity (between 252 W and 378 W) and at around 85% when we pulled 80% from its labeled capacity (504 W). At light load (20% load, i.e., 126 W) efficiency was still high at 84.4% and we were happy to see an 83.2% efficiency at full load.
Interesting enough this unit is not 80 Plus certified, but it could easily get the 80 Plus Bronze certification if the manufacturer wanted to.
Voltage regulation was another highlight from this product, with all voltages within 3% from their nominal values, i.e., voltages close to their nominal values that what is allowed (5%). This includes the -12 V output, which usually doesn’t like to stay so close to its nominal value. +5 V output exit this tight margin by only 0.01 V during tests one and two.
And finally we have noise and ripple, which were low all the time. Below you can see the results for test number five. As we always point out, the limits are 120 mV for +12 V and 50 mV for +5 V and +3.3 V and all numbers are peak-to-peak figures.

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Figure 15: +12V1 input from load tester at 632.4 W (63.8 mV).

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Figure 16: +12V2 input from load tester at 632.4 W (63.4 mV).

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Figure 17: +5V rail with power supply delivering 632.4 W (21.4 mV).

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Figure 18: +3.3 V rail with power supply delivering 632.4 W (19.6 mV).
Now let’s see if we could pull more than 630 W from this unit.