The fans in my Antec 900 are starting to squeak and they were never that quiet to begin with, so I'm going to replace them. I've kept the stock ones at low this whole time so I was thinking of picking ...

c) if you only use one of the 5.25 bays, replace the bottom 3 with a 120mm intake fan Now I want to qualify the above by saying that I do not have the case in front of me so my estimates of what size ...