The new MX series of power supplies from BFG features a modular cabling system, one 120-mm fan and one 80-mm fan that only kicks in when the temperature on the secondary heatsink is above 50º C. Let’s see if the 550 W model (MX-550 or BFGI550WMXPSU) is a good product.

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Figure 1: BFG MX-550.

By the way, power supplies from BFG MX series are internally identical to the ones from LS series. The difference between the two series lies on the presence of the modular cabling system and on the auxiliary 80-mm fan on the MX series, and also on the size of the main fan (120-mm on MX series but 135-mm on the LS series).

This power supply is 6 11/16” deep (17 cm), while we’ve seen some products on the same power range using a smaller form factor, 6 19/64” (16 cm) or even 5 ½” (14 cm) deep, but it is hard to make it smaller when a modular cabling system is used.

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Figure 2: BFG MX-550.

This unit has its main motherboard cable (20/24-pin connector) and the ATX12V/EPS12V cable (two ATX12V connectors that together form an EPS12V connector) coming directly from inside the power supply housing. They have a nylon sleeving that comes from inside the housing.

The modular cabling system has eight connectors, two reserved for the video card auxiliary power cables (lime green) and six for SATA and peripheral power connectors.

The unit comes with eight cables: one auxiliary power cable for video cards with a 6-pin connector, one auxiliary power cable for video cards with a 6/8-pin connector, one cable with three SATA power connectors, two cables with two SATA power plugs each, one cable with two standard peripheral power plugs and two cables with two standard peripheral power plugs and one floppy disk drive power plug each.

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Figure 3: Cables from the modular cabling system.

All wires used on this power supply are 18 AWG, which are adequate for a product on this power range.

MX-550 features active PFC, allowing BFG to sell it in Europe. As for efficiency, BFG says this unit has a minimum 80% efficiency.

This power supply is manufactured by Fore Point (one of the factories from Fortrex) and according to our contact at BFG it is based on their FP-165 design. This same design is currenty used by BFG LS series, so right now internally power supplies from these two series are identical. However, BFG will change the vendor from their LS series to Enhance Electronics in the near future, so they won't be internally identical forever.

Let’s now take an in-depth look inside this power supply.