It's not designed for that board.
Here's a very good review of that board you have. ASUS Rampage IV Extreme Motherboard Review - ASUS Republic of Gamers Rampage IV Extreme Intel X79 Motherboard - Legit Reviews
As you can see in the pics the maker is calling for a specific HS mounting format. The mounting studs are already installed. The HS you have was designed for a LGA775 platform. Basically a direct replacement for the Intel stock cooler as it mounts in the same push pin manner.
The main problem is like my DZ77GA-70K board there isn't a lot of free space around the CPU socket. It's going to have to be a tower. Make sure you have the clearance from the socket to the side of the case.
Now trying hard to not sound like a fan boy for Cooler Master, the Hyper 212 EVO is designed to fit the 2011 socket. And it's dirt cheap. $34.00usd at Newegg.