Intel Xeon E5 2609 's Advantages
Released 2 years late
Newer PCIe version (3 vs 2)
Higher base frequency (2.4GHz vs 1.9GHz)
More modern manufacturing process (32nm vs 45nm)
Lower TDP (80W vs 115W)
Opteron 6168 's Advantages
Larger L3 cache size (12MB vs 10MB)