The AX760i is an 80Plus Platinum
certified power supply so we did expect a very high electrical efficiency. During
our testing and at 50% load, the AX760i managed to reach 93.6% efficiency when
powered by a 230V source and 92.8% efficiency when powered by an 110V source.
The efficiency appears to be more stable when the unit is powered by a 230V
source, holding at 92.4% and above across the entire load range. When powered by
an 110V source, the efficiency drops at heavy loads but never goes below 91%.
Our noise level readings up to 30%
load were lower than 20dB(A) and essentially superficial, since the fan of the
AX760i starts only when the load is higher than about 35%. The pre-programmed
fan profile is obviously optimized for quiet operation as the fan will spin
very slowly, maintaining very low noise levels up to 80% load. Only at heavy
loads will the fan spin fast enough to reach clearly audible levels from 3ft
As the fan of the AX760i does not
spin at 20% load, the temperature reading at that point was essentially that of
the ambient air at the front side of the power supply. Even when the fan does
start, the temperature delta is very low albeit the fact that the fan speed is
very slow. Apparently the very high efficiency of the AX760i does the trick and
the power supply remains very cool without the need of strong active cooling.