be quiet! Power Zone 850 W Review

Name: be quiet! Power Zone 850 W
Brand: be quiet!

crmaris

on Mar 14th, 2014,

in Power Supplies.

Manufacturer: be quiet!

Performance Rating, Performance per Dollar, Noise & Efficiency Rating »

Ripple Measurements

You will see the ripple levels we measured on the main rails of the Power Zone 850 W in the following table. The limits are, according to the ATX specification, 120 mV (+12V) and 50 mV (5V, 3.3V, and 5VSB).

Ripple Measurements - Be quiet! Power Zone 850
Test	12 V	5 V	3.3 V	5VSB	Pass/Fail
20% Load	20.0 mV	10.4 mV	8.7 mV	6.5 mV	Pass
40% Load	22.8 mV	11.1 mV	10.9 mV	8.6 mV	Pass
50% Load	25.3 mV	12.9 mV	11.4 mV	10.3 mV	Pass
60% Load	26.1 mV	14.8 mV	11.5 mV	11.7 mV	Pass
80% Load	29.3 mV	18.3 mV	12.3 mV	13.9 mV	Pass
100% Load	32.1 mV	21.1 mV	13.4 mV	16.0 mV	Pass
110% Load	32.7 mV	20.4 mV	13.5 mV	16.2 mV	Pass
Crossload 1	21.9 mV	15.0 mV	15.8 mV	7.8 mV	Pass
Crossload 2	30.5 mV	16.6 mV	13.2 mV	10.4 mV	Pass

Ripple suppression was very good throughout the entire load range and on all rails. PSUs utilizing the ACRF topology usually aren't as strong in this area, but Power Zone broke with that tradition, proving that the right components and the design can even have this topology achieve excellent ripple suppression. You can rest assured that the Power Zone 850 W will feed your system components power of high quality.

We only noticed strange ripple spikes at +12V with the PSU at idle. However, those spikes are nothing to worry about since they were the result of a highly unrealistic scenario for a real system.

Ripple at Full Load

In the following oscilloscope screenshots, you can see the AC ripple and noise the main rails registered (+12V, 5V, 3.3V, and 5VSB). The bigger the fluctuations on the oscilloscope's screen, the bigger the ripple/noise. For all measurements, we set 0.01 V/Div (each vertical division/box equals 0.01 V) as the standard.