Mmmh maybe i'm stupid, or i dont know exactly how this rad is, but:
- cant you just turn it upside down so inlets face down ? (and keeping the fan above of course)
- if not is it moddable ? Dremel does wonders
Top/back/right position is quite good for 'flat' rads in YY case, because you save a lot of space and use natural thermal flow. you can even keep one of those 3"1/2 racks
If i had one of those 120mm equipped bastards i'd do it that way. Good luck with the hole saw man
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