They usually factor in the full size of the case when giving those measurements. The 9-10mm will make a big difference, even more so if you have to raise the fan up at all to compensate for RAM height. Assuming you can wedge it in there, you're looking at damaging the motherboard, CPU, and case. If you haven't bought the cooler yet, look for a Cryorig H7, it'll fit with a few mm to spare.