Cougar CMX V3 Series 850 W Review

Name: Cougar CMX V3 Series 850 W
Brand: Cougar

crmaris

on Oct 7th, 2013,

in Power Supplies.

Manufacturer: Cougar

Performance Rating, Performance per Dollar & Noise Rating »

Ripple Measurements

You will see the ripple levels we measured on the main rails of the CMX850 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 Cougar CMX850
Test	12 V	5 V	3.3 V	5VSB	Pass/Fail
20% Load	19.7 mV	21.6 mV	28.3 mV	10.2 mV	Pass
40% Load	31.6 mV	23.5 mV	29.0 mV	11.4 mV	Pass
50% Load	33.1 mV	24.8 mV	23.9 mV	16.0 mV	Pass
60% Load	39.4 mV	28.6 mV	29.8 mV	18.1 mV	Pass
80% Load	52.3 mV	29.9 mV	37.7 mV	27.1 mV	Pass
100% Load	73.9 mV	42.7 mV	41.8 mV	43.0 mV	Pass
110% Load	83.0 mV	43.4 mV	42.1 mV	50.7 mV	Fail
Crossload 1	25.4 mV	23.5 mV	30.7 mV	12.6 mV	Pass
Crossload 2	75.5 mV	38.3 mV	44.8 mV	32.0 mV	Pass

Ripple suppression was never this OEM's (HEC/Compucase) favorite area, and we can't help but wonder why they still struggle to produce good ripple suppression while other, more recently established OEMs already provide great working solutions in this area. The values shown on the table above may be inside ATX specifications, with the only exception being 5VSB during the overload test, but those values are still well above what we expect from a modern PSU. Cougar should pay more attention to the DC quality, implementing new methods that will effectively filter ripple at DC outputs.

Ripple at Full Load

You can see the AC ripple and noise that the main rails registered (+12V, 5V, 3.3V, and 5VSB) in the following oscilloscope screenshots. 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.