Be Quiet! PURE POWER L8 500 W Review

Name: Be Quiet! PURE POWER L8 500 W
Brand: Be Quiet!

crmaris

on Jul 4th, 2013,

in Power Supplies.

Manufacturer: Be Quiet!

Performance Rating & Performance per Dollar »

Ripple Measurements

You will see the ripple levels that we measured on the main rails of the L8-500W 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! L8-500W
Test	12 V	5 V	3.3 V	5VSB	Pass/Fail
20% Load	11.2 mV	9.5 mV	13.4 mV	13.1 mV	Pass
40% Load	16.8 mV	13.5 mV	13.5 mV	14.1 mV	Pass
50% Load	20.2 mV	16.1 mV	14.5 mV	17.0 mV	Pass
60% Load	23.7 mV	17.5 mV	15.5 mV	15.9 mV	Pass
80% Load	34.3 mV	23.2 mV	15.7 mV	16.5 mV	Pass
100% Load	51.1 mV	28.5 mV	16.3 mV	19.5 mV	Pass
110% Load	61.3 mV	31.0 mV	17.2 mV	21.4 mV	Pass
Crossload 1	16.7 mV	55.8 mV	16.2 mV	24.2 mV	Fail
Crossload 2	48.2 mV	21.9 mV	16.0 mV	16.6 mV	Pass

Overall ripple suppression is good for a unit that plays ball in the mainstream category, so we can't expect to see ripple below 20-30 mV with a full load at +12V. The failure in the CL1 test mainly happened because we followed the ATX guidelines for Haswell testing compatibility, as this unit is Haswell ready and compliant with the latest ATX v2.4 test; that is, according to Be Quiet!. The PSU would not have failed with the 1 A load we dialed in at +12V before Haswell compatibility testing so either purchase this unit for a non-Haswell system or disable the C6/C7 sleep states to avoid any problems. However, we will still deduct performance points for this failure because Be Quiet! states that the unit ought to work properly under CL1 test's conditions.

Ripple at Full Load

In the following oscilloscope screenshots, you can see the AC ripple and noise that 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 standard.