Intel Xeon E5 2609 v2 's Advantages
Released 3 years and 7 months late
Newer PCIe version (3 vs 2)
Higher base frequency (2.5GHz vs 2GHz)
Larger L3 cache size (10MB vs 8MB)
More modern manufacturing process (22nm vs 45nm)
Lower TDP (80W vs 85W)
Xeon EC5509 's Advantages
Higher specification of memory (1066 vs 3)