The electrical performance of the Be Quiet! Power Zone 850W power supply is good; not excellent but not bad either, considering the class of the power supply. Voltage regulation is at 2.2% on the 12V line and, slightly higher, at 2.6% on the 3.3V/5V lines, which are very good figures even for high performance units. Ripple suppression however could have been better. Even though the figures were much lower than the 120mV limit on the 12V line and 50mV limit on the 3.3V/5V lines, there are many high performance power supply designs can do much better than that.