LS and MX are sister power supply series from BFG, with models from MX series coming with a modular cabling system, a 120-mm fan and an auxiliary 80-mm fan on the rear (which only kicks in when the temperature on the secondary heatsink is above 50º C), while models from LS series use a 135-mm fan and no modular cabling system or second fan. Initially both series used the same internal design, however this is not entirely true anymore. All models from MX series are manufactured by Fore Point (one of the factories from Fortrex), but LS-450 and the new version of LS-550 (marked as “LS-550 (New)” on their website, being the model currently available on Newegg.com) are manufactured by Enhance. The old LS-550 and LS-680 are manufactured by Fore Point with the same design as models from MX series. According to BFG they will move all models from MX and LS to Enhance in the future, and when this happens units will be either released with new wattages (e.g. LS-700 instead of LS-680) or will have the name “New” added to their name.

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Figure 1: BFG MX-680 power supply.

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Figure 2: BFG MX-680 power supply.

BFG MX-680 is a relatively long unit, being 7” (18 cm) deep (counting the projection from the modular cabling connectors), using a 120-mm fan on its bottom and an 80-mm fan on its rear (which only turns on when the temperature on the secondary heatsink reaches 50º C) and featuring active PFC, of course.

The main motherboard cable (20/24-pin connector) and the ATX12V/EPS12V cable (two ATX12V connectors that together form an EPS12V connector) come from inside the power supply and have a nylon sleeving that also comes from inside the unit. They are long (23” or 58 cm each), which surely helps installing the unit inside a full tower case.

All other cables are available on the modular cabling system, which has eight connectors. MX-680 comes with nine cables, all measuring 21” (53 cm) between the end that goes on the modular cabling system and the first connector on the cable and 5 ½” (14 cm) between connectors. The cables included are:

• Two auxiliary power cables for video cards with one six/eight-pin video card auxiliary power connector and one six-pin video card auxiliary power connector each.
• One auxiliary power cable for video cards with one six-pin connector.
• One SATA power cable with four SATA power connectors.
• Two SATA power cables with two SATA power connectors each.
• One peripheral power cable with three standard peripheral power plugs and one floppy disk drive power plug.
• One peripheral power cable with two standard peripheral power plugs and one floppy disk drive power plug.
• One peripheral power cable with two standard peripheral power plugs.

All wires are 18 AWG, which is the correct gauge to be used. The number of cables is enough for a PC with up to two high-end video cards. The highlight here is the high number of SATA power plugs (eight).

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Figure 3: Cables.

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