The Corsair AX1200 power supply is one of the most efficient power supplies I have tested for OCC, but it gets better. The DC output voltage load regulation was almost perfect with all the rails maintaining their voltage within a 20mV window from zero to full load, whilst keeping ripple/noise levels well within the permitted levels. The Corsair AX1200 power supply could be the best power supply in this class at the moment and it will take some beating.