Xeon E7520 's Advantages
Lower TDP (95W vs 105W)
Intel Xeon E5 2650 v3 's Advantages
Released 4 years and 6 months late
Higher specification of memory (2133 vs 1333)
Newer PCIe version (3 vs 2)
Higher base frequency (2.3GHz vs 1.866GHz)
Larger L3 cache size (25MB vs 18MB)
More modern manufacturing process (22nm vs 45nm)