Right now my case is pretty loud with all my fans 3 80 mm, one 120 mm, and the stock hsf for my amd 3700+. And most of my fans are at about 30 db or so, and i wanted to know if replacing all my fans with stuff closer to 20 db would make much of a difference. And any brand or product recommendations would be great. Also which is better for cpu cooling arctic cooling or zalman.