Seasonic is a company very well known amongst advanced PC users and they are renowned as one of the best power supply manufacturers worldwide. The company serves many other companies as an OEM but also has their own lines of products. The 550W version of the G-series lineup will be contending today.
Seasonic supplies the G-series 550W unit inside an averagely sized, bright cardboard box with a serious artwork theme. Inside the box the power supply lays well protected between polystyrene foam pieces. The rear of the box is a small manual, with every bit of information regarding the power supply.
The G-series 550W unit is complemented by a bundle appropriate of its class. Inside the box we found the necessary A/C cable and mounting screws, black ties, three high quality cable straps, a case sticker and a manual.
As this is a modular power supply, Seasonic supplies the modular cables inside a fairly large reusable cloth pouch. The modular cables are all-black and sleeveless.
Visually, the G-Series 550W unit looks rather subtle and simplistic. The entire chassis is sprayed with a matte black paint and only the stickers on the sides of the power supply dissolve the darkness of it. Seasonic also replaced the typical fan cover with one that has a honeycomb grill implemented. The chassis is 160mm long, which will allow the G-Series to fit inside tight spaces.
Seasonic placed the sticker with the electrical specifications and certifications of this power supply on the right side of the chassis, where it will be visible from a windowed case panel. The series logo has also been sprayed on the rear side of the chassis. There are six modular cable connectors, two for PCI Express cables and four for Molex/SATA cables. The hardwired cables are normal sleeved cables with color-coded wires.
ADDA is the supplier of the AD1212MB-A70GL fan which is responsible for the cooling needs of the G-Series 550W power supply. It is a high speed 120mm fan with a ball bearing engine and capable of reaching a top speed of 2050RPM.
Seasonic is a company which manufactures the products of many other suppliers, therefore it is only natural that the G-series 550W unit is fully made in-house. The assembly quality is very good and the heatsinks are small but of high quality, providing ample dissipation surface. Seasonic made the filtering stage twice as strong as the ATX design guide requires, installing six Y capacitors, two X capacitors, three chokes and a MOV.
A Nippon Chemi-Con 390uF/420V capacitor and a coil of medium size are the passive components of the APFC circuit, with the active components, two transistors and a diode, attached to the heatsink near the edge of the PCB. The smaller heatsink near the main transformer holds the two primary inversion transistors, which form a half-bridge topology. On the secondary side of the transformer, the active components have been placed on the bottom side of the main PCB. DC to DC circuits create the 5V and 3.3V lines. The solid state capacitors are supplied by Enesol and the electrolytic capacitors come from Nippon Chemi-Con. The G-Series 550W unit also sports an LLC converter design, which improves efficiency.