Xeon E7 2850 's Advantages
Lower TDP (130W vs 135W)
Intel Xeon E5 2666 v3 's Advantages
Released 3 years and 7 months late
Higher specification of memory (2133 vs 1333)
Higher base frequency (2.9GHz vs 2GHz)
Larger L3 cache size (25MB vs 24MB)
More modern manufacturing process (22nm vs 32nm)