Ultra X4 850 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.
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.
+12V1 and +12V2 are the two independent +12V inputs from our load tester and during our tests both were connected to the power supply’s single +12 V rail.
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12V1 | 6 A (72 W) | 13 A (156 W) |
20 A (240 W) | 25 A (300 W) | 29 A (348 W) |
| +12V2 | 6 A (72 W) | 12 A (144 W) | 17 A (204 W) | 25 A (300 W) | 29 A (348 W) |
| +5V | 2 A (10 W) | 4 A (20 W) | 6 A (30 W) | 8 A (40 W) | 16 A (80 W) |
| +3.3 V | 2 A (6.6 W) | 4 A (13.2 W) | 6 A (19.8 W) | 8 A (26.4 W) | 16 A (52.8 W) |
| +5VSB | 1 A (5 W) | 1.5 A (7.5 W) | 2 A (10 W) | 2.5 A (12.5 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) | 0.5 A (6 W) |
| Total | 177.6 W | 357.4 W | 523.8 W | 699.7 W | 861.0 W |
| % Max Load | 20.9% | 42.0% | 61.6% | 82.3% | 101.3% |
| Room Temp. | 45.8° C | 46.6° C | 49.0° C | 48.5° C | 48.2° C |
| PSU Temp. | 47.8° C | 48.9° C | 51.4° C | 55.5° C | 56.8° C |
| Voltage Regulation | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
| AC Power | 217.4 W | 422.1 W | 619.0 W | 840.0 W | 1065.0 W |
| Efficiency | 81.7% | 84.7% | 84.6% | 83.3% | 80.8% |
| AC Voltage | 113.5 V | 111.9 V | 109.2 V | 107.6 V | 104.7 V |
| Power Factor | 0.933 | 0.974 | 0.984 | 0.988 | 0.991 |
| Final Result | Pass | Pass | Pass | Pass | Pass |
Ultra X4 850 W presented very good efficiency when delivering between 40% and 80% from its labeled power (between 340 W and 680 W), on the 83%-85% range. At 20% load (170 W) efficiency dropped to 81.7%, still a decent number. When delivering 850 W, it presented 80.8% efficiency, not the best but still above 80%.
There is something really weird about the 80 Plus certification from this power supply. The manufacturer says this unit has the standard 80 Plus certification, what makes sense according to our tests. But at 80 Plus website this unit is listed as 80 Plus Silver with a typical efficiency of 89% and average efficiency of 87%. Probably the sample Ultra sent to 80 Plus was internally different from the product they ended up manufacturing.
Voltages were always inside the maximum allowed (5% tolerance for the positive voltages and 10% for -12 V).
Ripple and noise levels were also below the maximum allowed. You can see the results below for test number five. All values are peak-to-peak figures and the maximum allowed is 120 mV for the +12 V outputs and 50 mV for the +5 V and +3.3 V outputs.
Figure 16: +12V1 input from load tester at 861.0 W (88.4 mV).
Figure 17: +12V2 input from load tester at 861.0 W (82.6 mV).
Figure 18: +5V rail with power supply delivering 861.0 W (20.6 mV).
Figure 19: +3.3 V rail with power supply delivering 861.0 W (15.6 mV).
Now let’s see if we could pull more than 850 W from this unit.