Efficiency is Bronze certified, and the PSU only features a few modular cables and is Haswell ready. It also packs all available protections, but CM unfortunately restricted its maximum operating temperature to 40°C, though we will, as per usual, test the unit at higher ambient.
|Cooler Master G550M Features & Specs|
|Max. DC Output||550W|
|Efficiency||80 PLUS Bronze|
|Intel Haswell Ready||Yes|
|Operating temperature||0°C - 40°C|
|Protections||Over Voltage Protection|
Under Voltage Protection
Over Power Protection
Over Temperature Protection
Over Current Protection
Short Circuit Protection
|Cooling||120 mm Double Ball-Bearing Fan (D12BH-12)|
|Dimensions||150 mm (W) x 86 mm (H) x 140 mm (D)|
|Compliance||ATX12V v2.31, EPS 2.92|
|Price at time of review (exc. VAT)||$59.99 (MSRP)|
The 120 mm fan uses double ball-bearings, which will increase its lifetime while producing a little bit more noise than a sleeve-bearing fan with similar characteristics. We also think that the fan is too powerful for such a low-capacity PSU, but CM apparently meant to stay on the safe side instead of skirting its edges given that efficiency isn't Platinum or even Gold which will, hence, lead to increased heat dissipation at higher loads. The unit's dimensions are pretty compact and its weight is low, too, and its price looks very good for its characteristics, which will easily boost its price/performance ratio if it performs well in our tests. CM lately follows a very aggressive pricing strategy for their new PSU products, which is to the benefit of all us consumers.
The +12V rail can deliver nearly 50 W less than the total capacity of the unit, which is strange since platforms utilizing DC-DC converters can normally deliver their full power output easily. The minor rails have enough power given the unit's capacity, and the same applies to the 5VSB rail.
|Cooler Master G550M Power Specs|
|Total Max. Power||550W|
Cables & Connectors, Power Distribution
There are enough available connectors for the power characteristics of this PSU; however, a couple more 4-pin Molex connectors would further increase its usability. Also, cable length is good, and the distance among connectors won't pose any problems if you install this unit into a small or medium-sized case. Finally, all connectors use standard 18AWG gauges, the size the ATX spec tends to recommend.
|ATX connector (550mm)||20+4 pin|
|4+4 pin EPS12V/ATX12V (600mm)||1|
|6+2 pin PCIe (500mm+120mm)||2|
|4 pin Molex (400mm+120mm+120mm) / FDD(+120mm)||3 / 1|
Since this PSU features a single +12V rail, we do not have anything to comment on about its power distribution.