er, snap. I forgot.

ASUS Silent Knight II CPU Cooler, Blue COOLER
Light, Socket 478/775/939/940/AM2/AM2+

You're going to need an LGA1366 Kit from ASUS to mount your cpu cooler.

Sorry about not noticing that. I tried looking for a bit, all I could find in sites actually selling the mounting bracket for your specific heatsink/fan were russian, and had the wrong variant.

Here's what I found on the ASUS global page.

http://www.asus.com/product.aspx?P_ID=g2wIezswzl8gW0FO

/me failed.

Your computer will still work fine (without overclocking) with the stock heatsink/fan. The insides just won't look as cool. So you could return the heatsink for a refund, or wait for the socket kit to come out. (I'd go for this one, the kits aren't very expensive)