BFG MX-680 Power Supply Review

Conclusions

Several manufacturers release higher capacity power supplies within the same series by simply replacing the secondary rectifiers with more powerful models. Fortunately this is not the case with BFG MX-680: the manufacturer replaces ALL components (PFC transistors, switching transistors and secondary rectifiers) with more powerful models compared to the 550 W product. This explains why we could pull up to 785 W from it.

If you are building a PC that is going to pull up to 544 W (80% of its labeled capacity), this power supply may be an option. At full load, however, efficiency drops below the 80% mark and we also had a huge ripple problem with the -12 V output when we pulled between 272 W and 408 W from it.

Another issue was that the auxiliary fan didn’t kick in automatically: we had to manually rotate it with the tip of a pencil in order to turn in on. This also happened with the 550 W model we reviewed.

A very important thing to keep in mind if you buy this unit: warranty. You have to register your power supply with BFG within 30 days of its purchase, otherwise you will only get a two-year warranty instead of the full five-year one. This is really tricky, as most users do not register their products with the manufacturer.

It comes with a somewhat attractive price tag – USD 130 –, but we think that there are better options on the market, like Seventeam ST-750Z-AF, which is cheaper, has a higher labeled wattage, also has a modular cabling system and provides a better performance.