Rosewill Fortress 550 W Review

Name: Rosewill Fortress 550 W
Brand: Rosewill

crmaris

on Jul 23rd, 2012,

in Power Supplies.

Manufacturer: Rosewill

Performance Rating & Performance per Dollar »

Ripple Measurements

In the following table, you will see the ripple levels that we measured on the main rails of the Fortress 550W. According to the ATX specification, the limits are 120 mV (+12V) and 50 mV (5V, 3.3V, and 5VSB).

Ripple Measurements Rosewill Fortress 550W
Test	12 V	5 V	3.3 V	5VSB	Pass/Fail
20% Load	19.3 mV	16.3 mV	15.6 mV	9.5 mV	Pass
40% Load	29.4 mV	19.3 mV	18.6 mV	11.3 mV	Pass
50% Load	37.7 mV	22.2 mV	23.7 mV	15.3 mV	Pass
60% Load	39.2 mV	25.1 mV	24.6 mV	16.7 mV	Pass
80% Load	42.3 mV	28.7 mV	28.6 mV	21.3 mV	Pass
100% Load	45.9 mV	29.4 mV	31.9 mV	24.7 mV	Pass
Crossload 1	44.5 mV	23.6 mV	24.2 mV	13.1 mV	Pass
Crossload 2	27.3 mV	23.3 mV	22.5 mV	18.4 mV	Pass

Ripple suppression, although not bad at all, is surely not among the strongest points of this PSU. In a high-performing platform such as this, we want the ripple to be below 40mV at +12V and close to 20mV or at least under 25mV on the minor rails. Some PSUs are ripple proof such as Super Flower, Seasonic, Enermax, and Delta.

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 to 0.01V) as standard.