Intel Xeon E5503 's Advantages
Lower TDP (80W vs 105W)
Intel Xeon E5 4620 v3 's Advantages
Released 5 years and 3 months late
Higher specification of memory (1866 vs 3)
Newer PCIe version (3 vs 2)
Larger L3 cache size (25MB vs 4MB)
More modern manufacturing process (22nm vs 45nm)