Testing – DC Output Voltage Regulation
To simulate real world operation, each power supply was connected to the load tester, supplied with 115 VAC, and allowed to burn-in for 24 hrs before voltage readings were taken. In this test we are interested in seeing how well a PSU can maintain the various output voltages while under a moderately heavy load. The DC output voltages were measured with a FLUKE digital multimeter at the ATX connector.
The ATX tolerance for voltages states how much each output (rail) is allowed to fluctuate. PC Power & Cooling specifies ±5% for all outputs except for the -12 V output, which is ±10%.
The following table lists the DC voltage regulation results for the two Silencer PSUs.
|
DC Output Regulation @ 115 VAC Input (Volts) | ||||||
|
Power Supply |
+3.3V |
+5V |
+12V |
-5V |
-12V |
5VSB |
|
Silencer 360 watt |
3.20 |
4.87 |
12.08 |
– |
-12.49 |
4.96 |
|
Silencer 410 watt |
3.20 |
4.87 |
12.11 |
– |
-12.62 |
4.96 |
As you can see, all of the DC outputs were held well within the ATX specification while operating under a 240 watt combined load. They were also rock solid with virtually no fluctuations during testing. I would prefer to see slightly higher values on the +3.3V lines however they are still well within tolerance.
Of particular interest are the three main power rails (+3.3V, +5V and +12V) and the 5VSB line. Maintaining these outputs at optimum levels is important to the reliable operation of any PC. If you push components (overclock/over-volt) then they become even more critical.
