Testing the Cooler Master Power Supply
The price of energy is increasing world wide, so any
reduction in the amount of power a computer draws is a welcome change in our
books. Power supplies which employ Power Factor Correction (PFC, or A-PFC) help
ensure efficient conversion of AC to DC voltage, and reduce the amount of energy
wasted as heat. The following power supply tests were all conducted with an
Extech Model 380803 Power Analyzer located between the mains 120AC supply and
the power supply, and with a 120W dummy load. Power jitter is measured with a
Mastech MS8230B Multimeter at the device power connectors. The test apparatus
and power meters are shown below.
Here is a picture of the PCSTATS test set we'll use to
evaluate the power supply. The power supply looking device is actually a 120W
dummy load.
Power Jitter Observations -
Motherboard |
|
Voltage jitter is read by accessing the power options
displayed in the motherboard BIOS, with the system obviously in an unloaded
state. *All voltages were read from the BIOS of an Asus A8N-SLI Premium
motherboard.
Power Jitter Observations
- Motherboard |
Listed Voltages |
Lower Voltage |
Upper Voltage |
Jitter |
+3.3V |
3.2V |
3.2V |
0.0V |
+5.0V |
4.96V |
4.98V |
0.02V |
+12V |
11.7V |
11.99V |
0.2V |
-12V |
11.99V |
11.99V |
0V |
-5.0V |
5.00V |
5.00V |
0V |
+5.0Vsb |
5.00V |
5.00V |
0V |
The Cooler Master
Power Pro 750W voltages do not fluctuate much as you can see here. The
last thing you want is for the power supply to give your system unreliable
power.
Power Jitter Observations - Multimeter
|
|
Voltage
jitter was read by a Mastech MS8230B Multimeter with the system in an unloaded
state. During testing the power supply is was still connected to a full computer
and voltage values.
Power Jitter Observations
- Multi-Meter |
Listed Voltages |
Lower Voltage |
Upper Voltage |
Jitter |
+3.3V |
3.3V |
3.3V |
0V |
+5.0V |
5.0V |
5.0V |
0V |
+12V |
12V |
12V |
0V |
Readings from the multimeter show that
the Cooler Master Real Power Pro is the real deal, voltages are rock solid.
When looking at the Seasonic Power Supply test results we see two values, wattage
and volt-amps. Since it might not be clear what they measure, here's a brief
overview.
The
volt-amp (VA) value is how much real power is being consumed by the power supply
being tested to provide the wattage (W) value. The higher the VA value is, the
more electricity is being used by the power supply. Because no electrical device
is 100% efficient, there will always be some loss when converting AC to DC. The
closer the volt-amps and wattage figures are to each other, the more efficient a
power supply is. This is called the Power Factor: wattage / volt-amps =
PF.
Since we're testing with a 120W dummy load, the
load on the power supply (wattage) should be as close to this figure as
possible. Anything above this load in apparent power describes the overhead and
wasted energy (given off as heat) for the particular power supply being tested.
For the unloaded tests, the wattage and volt-amp figures should be as close as
possible to one another. The lower the figures are, the less power is being
wasted.
Measurements were taken with an Extech 380803 Power
Analyzer.
Seasonic Power Load Tests |
Power Supply
Model |
Wattage |
Test
Type |
Loaded |
Unloaded |
Seasonic SuperTornado |
400 W (A-PFC) |
Active Power |
177 W |
6 W |
Apparent Power |
182 VA |
7 VA |
Vantec iON2 |
350 W |
Active Power |
192 W |
10 W |
Apparent Power |
277 VA |
21 VA |
Antec TruePower 330 |
330 W |
Active Power |
195 W |
22 W |
Apparent Power |
289 VA |
38 VA |
Ultra X-Connect Green UV 500W |
500 W |
Active Power |
193W |
22 W |
Apparent Power |
307 VA |
40 VA |
AOpen Silent Power AO400-12AHN |
400 W |
Active Power |
179W |
9 W |
Apparent Power |
275 VA |
18 VA |
Seasonic S12-430 |
430 W (A-PFC) |
Active Power |
179W |
6W |
Apparent Power |
180VA |
9VA |
PC Power and Cooling Turbo-Cool 510 Express/SLI |
510 W (A-PFC) |
Active Power |
200 W |
29 W |
Apparent Power |
202 VA |
32 VA |
HEC Ace Power 580UB |
580 W |
Active Power |
183 W |
12 W |
Apparent Power |
272 VA |
26 VA |
HEC Win 550UB |
550 W |
Active Power |
184W |
10W |
Apparent Power |
263VA |
22VA |
Akasa PowerPlus AK-P550FF |
550 W (A-PFC) |
Active Power |
194W |
38W |
Apparent Power |
197VA |
40VA |
AOpen Prima Power AO700-12ALN |
700 W (A-PFC) |
Active Power |
172W |
3W |
Apparent Power |
181VA |
9VA |
PC Power & Cooling Turbo-Cool 1KW |
1000 W (A-PFC) |
Active Power |
205W |
25W |
Apparent Power |
207VA |
32VA |
Seasonic S12 600 |
600 W (A-PFC) |
Active Power |
164W |
7W |
Apparent Power |
173VA |
9VA |
Mushkin Enhanced XP-650 |
650 W |
Active Power |
192W |
22W |
Apparent Power |
279VA |
43VA |
Seasonic S12 Energy Plus SS-650HT |
650 W (A-PFC) |
Active Power |
150W |
7W |
Apparent Power |
150VA |
10VA |
Seasonic M12 700W |
700 W (A-PFC) |
Active Power |
161W |
8W |
Apparent Power |
165VA |
11VA |
Corsair HX620W |
620 W (A-PFC) |
Active Power |
171W |
8W |
Apparent Power |
173VA |
12VA |
Zalman
ZM600-HP |
600 W (A-PFC) |
Active Power |
173W |
5W |
Apparent Power |
175VA |
9VA |
HEC Zephyr 650 |
650 W (A-PFC) |
Active Power |
185W |
12W |
Apparent Power |
190VA |
17VA |
GlacialPower GP-PS550BP |
550 W |
Active Power |
178W |
6W |
Apparent
Power |
269VA |
17VA |
Cooler Master Real Power Pro 750W |
750
W (A-PFC) |
Active Power |
158W |
6W |
Apparent Power |
163VA |
9VA | |
Cooler Master quotes 80% efficiency on its packaging, but here the power
supply only reaches 76% in our tests. That's a good result, and perhaps efficiency is better
at higher load values... If you're looking to lighten the electricity bill at
the end of each month, the Cooler Master Real Power Pro 750W should
definitely garner some consideration.
|