Thermaltake Toughpower Grand 750 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 the behavior of the reviewed unit 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 powers listed for each test, you may find a different value than what is posted under “Total” below. Since each output can have a slight variation (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. In the “Total” row, we are using the real amount of power being delivered, as measured by our load tester.
The +12VA and +12VB inputs listed below are the two +12 V independent inputs from our load tester. 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 |
| +12VA | 5 A (60 W) | 11 A (132 W) | 16 A (192 W) | 22 A (264 W) | 27 A (324 W) |
| +12VB | 5 A (60 W) | 10 A (120 W) | 16 A (192 W) | 21 A (252 W) | 27 A (324 W) |
| +5V | 2 A (10 W) | 4 A (20 W) | 6 A (6 W) | 8 A (40 W) | 10 A (50 W) |
| +3.3 V | 2 A (6.6 W) | 4 A (13.2 W) | 6 A (19.8 W) | 8 A (26.4 W) | 10 A (33 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 | 148.6 W | 299.4 W | 448.4 W | 595.8 W | 743.1 W |
| % Max Load | 19.8% | 39.9% | 59.8% | 79.4% | 99.1% |
| Room Temp. | 43.2° C | 42.9° C | 45.7° C | 48.0° C | 48.3° C |
| PSU Temp. | 47.7° C | 47.8° C | 48.2° C | 49.2° C | 53.4° C |
| Voltage Regulation | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
| AC Power | 167.4 W | 331.8 W | 503.9 W | 684.0 W | 868.0 W |
| Efficiency | 88.8% | 90.2% | 89.0% | 87.1% | 85.6% |
| AC Voltage | 114.5 V | 112.8 V | 110.0 V | 108.8 V | 106.6 V |
| Power Factor | 0.974 | 0.991 | 0.995 | 0.997 | 0.998 |
| Final Result | Pass | Pass | Pass | Pass | Pass |
The Thermaltake Toughpower Grand 750 W can really deliver its labeled wattage at high temperatures.
Efficiency was extremely high, above 88% at light load (20% load, 150 W) and above 85% at full load, peaking 90.2% at 40% load (300 W). These are good results but since it is an 80 Plus Gold unit, it should present efficiency above 87% at full load. Time and time again we see this happening, because the 80 Plus certification tests are done at a room temperature of only 23° C, while we tested this particular unit at 48° C, and efficiency drops with temperature.
Voltages were always inside the allowed range, but during tests four and five the +5 V and +3.3 V outputs were touching the lower limit (+4.75 V and +3.13 V, respectively).
Noise and ripple levels were always extremely low. Below you can see the results for the power supply outputs during test number five. The maximum allowed is 120 mV for +12 V and -12 V outputs, and 50 mV for +5 V and +3.3 V outputs. All values are peak-to-peak figures.
Figure 19: +12VA input from load tester during test five at 743.1 W (21.4 mV)
Figure 20: +12VB input from load tester during test five at 743.1 W (49.6 mV)
Figure 21: +5V rail during test five at 743.1 W (11.4 mV)
Figure 22: +3.3 V rail during test five at 743.1 W (19.6 mV)
Let’s see if we can pull even more from the Thermaltake Toughpower Grand 750 W.