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 and +12V3 rails and the +12V2 input was connected to the power supply +12V2 rail.
Input | Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
+12V1 | 5 A (60 W) | 11 A (132 W) | 16 A (192 W) | 21 A (252 W) | 25 A (300 W) |
+12V2 | 5 A (60 W) | 10 A (120 W) | 15 A (180 W) | 20 A (240 W) | 25 A (300 W) |
+5V | 1 A (5 W) | 2 A (10 W) | 4 A (20 W) | 6 A (30 W) | 10 A (50 W) |
+3.3 V | 1 A (3.3 W) | 2 A (6.6 W) | 4 A (13.2 W) | 6 A (19.8 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 | 138.9 W | 280.8 W | 418.4 W | 554.9 W | 696.7 W |
% Max Load | 19.8% | 40.1% | 59.8% | 79.3% | 99.5% |
Room Temp. | 45.1º C | 46.9º C | 48.7º C | 47.8º C | 49.9º C |
PSU Temp. | 45.7º C | 47.1º C | 49.2º C | 50.2º C | 51.1º C |
Voltage Stability | Pass | Pass | Pass | Pass | Pass |
Ripple and Noise | Pass | Pass | Pass | Failed on -12 V and +5VSB | Failed on +12 V, -12 V and +5VSB |
AC Power | 163.4 W | 324.2 W | 486.0 W | 654.0 W | 842.0 W |
Efficiency | 85.0% | 86.6% | 86.1% | 84.8% | 82.7% |
AC Voltage | 111.2 V | 110.6 V | 109.7 V | 107.1 V | 104.9 V |
Power Factor | 0.983 | 0.987 | 0.990 | 0.993 | 0.994 |
Final Result | Pass | Pass | Pass | Pass | Pass |
Cooler Master UCP 700 W could really deliver its labeled power at 50º C, which is great.
The highlight from UCP 700 W is clearly efficiency, which was between 84.8% and 86.6% when we pulled up to 80% from its labeled load (i.e., up to 560 W). At full load (700 W) efficiency dropped to 82.7%, still a good number. It is important to keep in mind that we use a more rigorous methodology then the 80 Plus organization, especially regarding the temperature: they collect data at 23º C (a temperature impossible to be achieved inside a PC), while we collect data at a room temperature of at least double this number (which we consider more realistic; the higher the temperature, the lower the efficiency). This explains why even though this unit is 80 Plus Silver certified we saw efficiency of 82.7% and not 85% as expected.
All voltages were within 3% of their nominal values, except -12 V during test number one (3.5%, still inside the 10% margin this output has) and +5 V during test number five (4%, still inside the 5% margin this output has).
The main problem with Cooler Master UCP 700 W is electrical noise. Noise on -12 V was always high, starting at 76.4 mV during test number one and increasing until it got above the maximum allowed (120 mV) on tests number four (125.8 mV) and five (148.6 mV). Noise on +5VSB was touching the 50 mV limit on test number three (45.6 mV) and surpassed it during tests four (55.6 mV) and five (86.2 mV). These results alone wouldn’t be much of a problem, but +12 V was also very noisy, jumping from around 80 mV on test number three, to around 100 mV during test four and surpassing the 120 mV limit during test number five (124.4 mV on +12V1 and 129.4 mV on +12V2). Noise level on +5 V and +3.3 V outputs were within the proper range, though. All values are peak-to-peak and below you can see the main outputs during test five.
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Figure 16: +12V1 input from load tester at 696.7 W (124.4 mV).
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Figure 17: +12V2 input from load tester at 696.7 W (129.4 mV).
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Figure 18: +5V rail with power supply delivering 696.7 W (20.8 mV).
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Figure 19: +3.3 V rail with power supply delivering 696.7 W (26.2 mV).
We tested the over current protection circuit by increasing current on +12V2 rail until the power supply would shut down. This happened when we tried to pull more than 32 A from it.
For our traditional overload tests we increase currents while maintaining all outputs inside the proper range as set by the ATX specification. Since this unit was already with noise levels outside the maximum allowed when delivering 700 W, we decided not to overload it.
