Intel Xeon E5 2609 v3 's Advantages
Released 2 years and 6 months late
Higher specification of memory (1600 vs 3)
More modern manufacturing process (22nm vs 32nm)
Lower TDP (85W vs 115W)
Intel Xeon E5 2665 's Advantages
Higher base frequency (2.4GHz vs 1.9GHz)
Larger L3 cache size (20MB vs 15MB)