PSU Inside

Opening the PSU voids your warranty, and to make sure Cooler Master can detect this in case of an RMA, they added this small sticker on top of one of the four screws. Getting the sticker off with a razor blade is VERY hard without destroying the sticker. I couldn't do it.


All our warranty losing efforts were for nothing. There are no trimmers or other interesting parts inside. But seeing how clean everything is, gives me a feeling that the people who designed this unit know their stuff.

Test Equipment

• The PSU is connected to an APC SmartUPS which supplies clean 220V input.
• AC current is measured using a Peaktech 4010 desktop RS232 multimeter with 0.02A accuracy.
• To measure DC output voltages of the PSU we use a 20-bit data acquisition system calibrated to 10uV accuracy.
• Power Factor is measured using a generic Power Efficiency Meter.
• Measurements for Ripple Voltage were obtained using a 30 MHz HAMEG Analog/Digital Oscilloscope.

Sound level measurements are performed with an IEC Type 2 Sound level meter and this setup.
It consists of three high-power resistors and a Socket A motherboard. The motherboard creates a small load which makes sure the PSU turns on (some PSUs require a minimum load). Since there is no hardware installed in the motherboard, its power draw is negligible. The three resistors create a static load of 320W (120W @ 12V + 50W @ 5V + 150W @ 12V) - a typical high-performance system. This setup is also used to determine the power conversion efficiency of the PSU.