Intel Xeon E5 4640 's Advantages
Larger L3 cache size (20MB vs 10MB)
Lower TDP (95W vs 105W)
Intel Xeon E5 2623 v3 's Advantages
Released 2 years and 4 months late
Higher specification of memory (1866 vs 3)
Higher base frequency (3GHz vs 2.4GHz)
More modern manufacturing process (22nm vs 32nm)