Xeon E7 2870 's Advantages
Larger L3 cache size (30MB vs 25MB)
Lower TDP (130W vs 135W)
Intel Xeon E5 1681 v3 's Advantages
Released 3 years and 5 months late
Higher specification of memory (2133 vs 1333)
Higher base frequency (2.9GHz vs 2.4GHz)
More modern manufacturing process (22nm vs 32nm)