There's pics of an H80i in the case a few pages back, which is a 38mm thick rad. The thicker the rad, the tighter the fit, but that doesn't mean you can't make it work. Try it and see.Necere Will using a 38mm think rad be pushing it i have a 34mm one sitting here but im thinking of changing it as i like the other one more? Are the fans better off pushing air out of the case or sucking air in?