Thermaltake Litepower 450 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 the +12V1 input was connected to the power supply +12V1 (main motherboard connector and peripheral power connectors) while the +12V2 input was connected to the power supply +12V2 rail (ATX12V connector).
| Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| +12V1 | 3 A (36 W) | 6.5 A (78 W) | 9.5 A (114 W) | 13 A (156 W) | 16 A (192 W) |
| +12V2 | 3 A (36 W) | 6.5 A (78 W) | 9.5 A (114 W) | 13 A (156 W) | 16 A (192 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 A (5 W) | 1.5 A (7.5 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) | 0.5 A (6 W) |
| Total | 91.1 W | 182.9 W | 271.3 W | 364.2 W | 445.0 W |
| % Max Load | 20.2% | 40.6% | 60.3% | 80.9% | 98.9% |
| Room Temp. | 45.5° C | 46.3° C | 46.5° C | 47.0° C | 47.4° C |
| PSU Temp. | 46.8° C | 47.3° C | 47.4° C | 47.9° C | 48.9° C |
| Voltage Stability | Pass | Pass | Pass | Pass | Pass |
| Ripple and Noise | Pass | Pass | Pass | Pass | Pass |
| AC Power (1) | 103 W | 203 W | 303 W | 414 W | 517 W |
| Efficiency (1) | 88.4% | 90.1% | 89.5% | 88.0% | 86.1% |
| AC Power (2) | 110.4 W | 217.0 W | 318.2 W | 433.7 W | 539.5 W |
| Efficiency (2) | 82.5% | 84.3% | 85.3% | 84.0% | 82.5% |
| AC Voltage | 112.7 V | 111.5 V | 110.8 V | 109.6 V | 108.5 V |
| Power Factor | 0.978 | 0.964 | 0.968 | 0.973 | 0.976 |
| Final Result | Pass | Pass | Pass | Pass | Pass |
Updated 06/24/2009: We re-tested this power supply using our new GWInstek GPM-8212 power meter, which is a precision instrument and provides accuracy of 0.2% and thus presenting the correct readings for AC power and efficiency (resul
ts marked as “2” on the table above; results marked as “1” were measured with our previous power meter from Brand Electronics, which isn’t so precise as you can see). We also added the numbers for AC voltage during our tests, an important number as efficiency is directly proportional to AC voltage (the higher AC voltage is, the higher efficiency is). Also, manufacturers usually announce efficiency at 230 V, which usually inflates efficiency numbers. We added power factor (PF) numbers as well. These numbers measure the efficiency of the power supply active PFC circuit. This number should be as close to 1 as possible. The active PFC circuit from this unit is good but could be better, because easily see other units with active PFC achieving a power factor of 0.99.
Efficiency was great, especially for an entry-level product: between 84% and 85% if you pull between 40% and 80% from its labeled power (between 180 W and 360 W). Under light load (20% load, i.e., 90 W) and full load (450 W) efficiency was at 82.5%, which is still fair enough.
Electrical noise was always at low levels, between 30.8 mV (test one) and 54.4 mV (test five) on +12V1, between 22.8 mV (test one) and 43.4 mV (test five) on +12V2, between 12.6 mV (test one) and 15.4 mV (test five) on +5 V and between 12.8 mV (test one) and 20.8 mV (test five) on +3.3 V. These numbers are peak-to-peak values and the maximum allowed is of 120 mV on +12 V outputs and 50 mV on +5 V and +3.3 V outputs.
Now let’s see if we could pull more than 450 W from this unit.