Xeon L5639 's Advantages
Higher base frequency (2.133GHz vs 1.9GHz)
Lower TDP (60W vs 115W)
Intel Xeon E7 4820 v3 's Advantages
Released 4 years and 4 months late
Higher specification of memory (1866 vs 1333)
Newer PCIe version (3 vs 2)
Larger L3 cache size (25MB vs 12MB)
More modern manufacturing process (22nm vs 32nm)