The old overclockers I know don't mount the heat exchanger inside the case.
http://www.popularmechanics.com/technology/how-to/build-pc/4213273 as an example.
i have an AMD FX-6200 rinning stock clocks, with the stock heat sink. i was impatient and skimped out on my case, so i can only fit a 120mm liquid cooler in it.
I'm wanting to OC my processor to as close to 5g's as possible. is there any cooler that will fit in my system (whether it be air or liquid) that can handle that high of an overclock? in regards to air cooling, i don't mind doing away with my side panel to fit a large cooler. i also already have low profile ram, so size of the cooler doesn't matter.