I was happier fitting the stock Intel cooler that came with the CPU. At least it fitted in seconds and didn't look like it could fall off at any moment. The Arctic cooler went back in the box.

Installed in an NZXT H500 with 1x Arctic p12 ... to pull air through, as it wouldn't fit due to me using all 4 RAM slots on my motherboard. Other than that, excellent cooler.