|Mushkin HP-580AP Modular 580W PSU|
|Reviews - Featured Reviews: Power|
|Written by Olin Coles|
|Monday, 04 December 2006|
Page 6 of 7
Voltage Regulation & Ripple Test Results
In the test results below, it will be necessary to explain what you are viewing. In each image the AC power ripple is represented by the yellow trace line making up the waveform. While every personal computer power supply unit available to the retail market has some degree of measurable AC power ripple, it is most important that measurable AC ripple is very minor and does not create a large peak to peak voltage (Vpp) distortion. Stable, well-regulated power is critical to system stability and hardware longevity.
AC Ripple at Light Idle Load
The waveform image above shows the AC power ripple under light idle load, which measured 24.9 mV. Note that there are several minor ripples above and below the baseline, and many major ripples, all of which occur inside of a 1ms recording frame. The waveform data recorded during the light idle load measurement is displayed in the chart below:
AC Ripple Waveform Data at Light Idle Load
The waveform information above describes the actual measurements at light idle load. The average AC RMS ripple was 24.9 mV under light idle load, which is high. Here are the average AC RMS ripple measurments under light idle load for power supplies we have recently tested:
The waveform image below shows the AC power ripple under heavy load, which measured 12.70 mV. Note that there are several minor ripples above and below the baseline, and only a few major ripples, all of which occur inside of a 1ms recording frame. Now let's see how this power supply performs under heavy load:
AC Ripple at Heavy Load
Under heavy load, the Mushkin HP-5880AP measured an average AC RMS ripple of 61.0 mV, which is considerably high. For more specific readings, see the waveform data table below.
AC Ripple Waveform Data at Heavy Load
The Mushkin HP-5880AP offered very poor results in the idle readings, and they only got worse into the heavy load tests. Here are the average AC RMS ripple measurments under heavy load for other power supplies we have recently tested:
The power dropped down to no less than 11.88V, which means that even under heavy load there is very little chance that system stability will be affected. Under light idle load conditions the DC regulation averaged 0.38 Vpp, and the deviation increased to .50 Vpp under heavy load. The DC regulation data recorded at light and heavy load is displayed in the chart below:
DC Voltage Regulation Waveform Data at Light Idle and Heavy Load
Many of the power supplies we test here at Benchmark Reviews have DC voltage regulation measuring above the 12V baseline more often than below. For obvious reasons, the diversion from the 12V baseline with increased voltage is more preferred than below it since dropping too far under 12V will cause a system to power off or recycle. Plainly put, no power supply is ever perfectly centered at 12V DC; instead they most often maintain a DC mean voltage higher than they are regulated at.