Intel Xeon E5 2609 's Advantages
Lower TDP (80W vs 165W)
Intel Xeon E7 8891 v3 's Advantages
Released 3 years and 3 months late
Higher specification of memory (1866 vs 3)
Higher base frequency (2.8GHz vs 2.4GHz)
Larger L3 cache size (45MB vs 10MB)
More modern manufacturing process (22nm vs 32nm)