Intel Xeon E5 2609 v2 's Advantages
Released 1 years and 6 months late
Higher base frequency (2.5GHz vs 2.4GHz)
More modern manufacturing process (22nm vs 32nm)
Lower TDP (80W vs 115W)
Intel Xeon E5 2665 's Advantages
Larger L3 cache size (20MB vs 10MB)