first of all its 1u, not iu.
second, he said he wants a corb but is paranoid about the noise. that means he is hesitant because hes afraid the crystal orb will make too much noise over the stock one.
my suggestion, and what im going to do soon is get one of the 1u coolers. theyre a much more serious unit than the pretty little orb thingies and cost almost the same.
the best one is supposed to be by cooljag. newegg has 2 different ones. the original($16) and then a newer one(17) thats a bit smaller. 62mm square i think, versus something like 62x68. one thing though, is that you need to cut a piece off of the corner of anything this much larger than 40x40, because some capacitors on the 8500 will interfere with it.
also, i bet any of these will be louder than youd like. you could switch the fan to a quieter thicker 60mm one if it wouldnt interfere with PCI cards. or you could go to the anandtech article from a while back that did a roundup of a bunch of 1u HSFs and see what is quietest.
ill probably grab the newer cooljag unit because i like ordering from newegg and they have it cheap. i dont care about noise at all because i wont be able to hear it over everything else anyways.