make sure the correct pins line up on your fan. Last time I checked the fan plug the pins were 'reversed' as opposed to a standard 3-pin connection. Match the red and black wires, yellow will have no connection.
Thanks! How can I check that though when all the cables are just plain black?
Oh Damn.....one of those....do you have another fan with the same connector that you can use to compare? Otherwise try to look up the pinout of a motherboard fan header and that should tell you. I'd do it but I'm on my phone and it's kind of a pain in the ass.