Intel Xeon E5 2620 v3 's Advantages
Larger L3 cache size (15MB vs 13.75MB)
Lower TDP (85W vs 140W)
Intel Xeon W 2155 's Advantages
Released 2 years and 11 months late
Higher specification of memory (2666 vs 1866)
Higher base frequency (3.3GHz vs 2.4GHz)
More modern manufacturing process (14nm vs 22nm)