Intel Xeon E3 1225 v2 's Advantages
Lower TDP (77W vs 140W)
Intel Xeon E5 1620 v3 's Advantages
Released 2 years and 4 months late
Higher specification of memory (DDR4-2133 vs DDR3)
Higher base frequency (3.5GHz vs 3.2GHz)
Larger L3 cache size (10MB vs 8MB)