Intel Xeon E3 1285 v6 's Advantages
Higher base frequency (4.1GHz vs 2.3GHz)
Lower TDP (79W vs 215W)
Xeon 6556P B 's Advantages
Released 7 years and 6 months late
Higher specification of memory (6400 vs 4)
Newer PCIe version (5 vs 3)
Larger L3 cache size (144MB vs 8MB)
More modern manufacturing process (5nm vs 14nm)