Xeon E7520 's Advantages
Lower TDP (95W vs 120W)
AMD EPYC 7251 's Advantages
Released 7 years and 3 months late
Higher specification of memory (2400 vs 1333)
Newer PCIe version (3 vs 2)
Higher base frequency (2.1GHz vs 1.866GHz)
Larger L3 cache size (32MB vs 18MB)
More modern manufacturing process (14nm vs 45nm)