Intel Xeon E5 2609 v2 's Advantages
Released 1 years and 4 months late
More modern manufacturing process (22nm vs 32nm)
Lower TDP (80W vs 130W)
Intel Xeon E5 4650 's Advantages
Higher base frequency (2.7GHz vs 2.5GHz)
Larger L3 cache size (20MB vs 10MB)