I have the older Antec 900 case and recently swapped out all the stock fans with Silenx fans (which are impressive) in order to cut down on fan noise. I also cleaned my case of dust and set the 200mm stock fan to a low setting but am still getting noise from it. It's possible the bearings are going bad or there's dust inside (it is 7 years old). I've seen tutorials on getting the fan out (http://www.tomshardware.com/forum/245308-28-antec-removal-200mm-replacement) but my real question is: am I stuck with another stock Antec 200mm fan as a replacement or can I get something else that will fit. Before answering please take a look at the fan and you'll notice the shape is not perfectly round, more like the sides are cut off: http://www.antec.com/images/400/200mm_fan.jpg