No its performance is almost equivalent to the Intel Box cooler. Its not sufficient for a 'k' Intel CPU.
Caution statement from Noctua on the NH-L9i:
http://noctua.at/en/nh-l9i
Caution: The NH-L9i is a highly-compact low-profile quiet cooler designed for use in small form factor cases and HTPC environments. While it provides first rate performance in its class, it is not suitable for overclocking and should be used with care on CPUs with more than 65W TDP (Thermal Design Power). Please consult our TDP guidelines to find out whether the NH-L9i is recommended for your CPU.