Intel Xeon E3 1220 's Advantages
Lower TDP (80W vs 165W)
Intel Xeon Gold 5515 's Advantages
Released 12 years and 8 months late
Higher specification of memory (4800 vs 3)
Newer PCIe version (5 vs 3)
Higher base frequency (3.2GHz vs 3.1GHz)
Larger L3 cache size (22.5MB vs 8MB)
More modern manufacturing process (10nm vs 32nm)