Intel Xeon E5 2420 's Advantages
Lower TDP (95W vs 250W)
Intel Xeon Platinum 9221 's Advantages
Released 6 years and 11 months late
Higher specification of memory (DDR4-2933 vs DDR3)
Higher base frequency (2.1GHz vs 1.9GHz)
Larger L3 cache size (71.5MB vs 15MB)
More modern manufacturing process (14nm vs 32nm)