Intel Xeon E5 2670 's Advantages
Released 4 years and 4 months late
Newer PCIe version (3 vs 2)
Higher base frequency (2.6GHz vs 2GHz)
More modern manufacturing process (32nm vs 45nm)
Xeon E5405 's Advantages
Higher specification of memory (3 vs 3)
Lower TDP (80W vs 115W)