Xeon EC5539 's Advantages
Higher specification of memory (1333 vs 3)
Lower TDP (65W vs 95W)
Intel Xeon E5 4640 's Advantages
Released 2 years and 3 months late
Newer PCIe version (3 vs 2)
Higher base frequency (2.4GHz vs 2.266GHz)
Larger L3 cache size (20MB vs 4MB)
More modern manufacturing process (32nm vs 45nm)