OCModShop - "The Propeller Dual-Fan card is such a simple idea, I can't believe this is the first time I have seen something like this (ie. not a black dinky thing). The idea is that you simply insert the fan into an empty PCI slot in your computer/motherboard, placing it where you believe you need extra cooling. The dual fans then blow air directly onto the area directly beside the card in the hopes that added overclocking and heat reduction will occur. The fan gets it's power from a standard 12v plug (4 pin) that daisy chains any one of the other powered items in your case."