BFG MX Series 550W PSU

MX Series

BFG's MX Series looks pretty smart. It's not shiny like the ES Series we checked out last year, although it still features the stamped BFG brand logo in the side and a sleek black look all over. It's a shame BFG didn't pay attention to the detail and match the screw colour with the rest of the unit though.

It's slightly longer than other PSUs of the same wattage too, and as such feels heavy enough but still a bit "empty" - especially when we check inside. The all black design might be considered either unintrusively fitting to a tidy build, or a little boring when up against the new ruggedized or two tone finishes other manufacturers have adopted.

The fan appears small, but it's actually just a regular 12cm sleeve bearing, rather than the enlarged 13.5cm many other companies use. Arguments in favour of using the more popular 12cm fans are that the manufacturing to build a quality 12cm fan has been around longer and there's more variety, however 13.5cm fans have also been made for a few years now and many companies use them without serious issue.


At the one end is the usual honeycomb grill to exhaust the heat, along with the power socket and rocker switch, while the other unusually features a 80mm fan pushing air through, as well as the eight modular sockets and fixed ATX and 8-pin 12V EPS power cable. The 80mm fan only turns on when the temperature hits 50ºC though - that's typically very heavy load and a hot case, but it does beg the question why BFG feels the needs to include one "just in case" whereas other companies do not.

BFG uses four 12V rails, each capable of 20A, although overall this is limited to 500W out of the maximum continuous 550W output - 91 per cent of the total. The internal design for all four rails is, like normal, from a single 12V source split and individually controlled by over current protection, but this is not a DC-DC device so 3.3V and 5V have their own, smaller transformer.


BFG's modular plugs are nice and chunky, standing out clearly against the sharp square edges that make up the rest of the power supply. The eight are topped off by two green plugs for the PCI-Express graphics connectors - as expected these correspond to two other green connectors among the modular cables, while the rest are for SATA and Molex peripherals.

The plugs are very well fitting, with strong clips that certainly won't easily yank free, but also resist removal just a little.