[Khledar]

It's my understanding that the additional circuitry is used to "clean" the power draw, from various interferences shown on since87's osciliscope pics. If you dont have any sensitive devices running on your power supply, and the power supply its self is able to handle the fluxuations in the power draw I doubt it would be a problem. I'm running the pump sans additional circuitry right now, and I haven't had any power problems - It puts a small constant draw on my 12V line but that's about it - I've isolated it to one of the "molex chains" as suggested so the only thing running on that chain is a couple fans and the pump, the fans are cool with it and so it the pump.