i'm about to pickup an antec three hundred for my new build but not sure on this one thing. will the front fan cages accomodate a 120 x 25 or will they take a 120 x 38 or either? i've been researching and have found conflicting information in the reviews i've been reading. also, in my process of selecting fans, i've noticed some are rated as a variable speed (some with and some without an inline switch). are the fans that are rated at a fixed speed going to burn up if i adjust their voltage though a controller? thanks for your advice.