I was looking at AIO as i've never done a custom loop basically after getting my tape measure out I have 55mm clearance for the rad in the top I measured from the top fan to the motherboard
EDIT: I have just finished putting all my components in my new case and wow is all I can say for £52 its wide enough for my Noctua NH-D14 and supports water cooling AIO's what a bargain of a case