Intel Xeon E5 4620 's Advantages
Released 2 years and 2 months late
Newer PCIe version (3 vs 2)
Higher base frequency (2.2GHz vs 2GHz)
Larger L3 cache size (16MB vs 4MB)
More modern manufacturing process (32nm vs 45nm)
Intel Xeon E5503 's Advantages
Lower TDP (80W vs 130W)