Intel Xeon E5 4640 v3 's Advantages
Released 3 years and 3 months late
Higher specification of memory (1866 vs 3)
Larger L3 cache size (30MB vs 10MB)
More modern manufacturing process (22nm vs 32nm)
Lower TDP (105W vs 130W)
Intel Xeon E5 2643 's Advantages
Higher base frequency (3.3GHz vs 1.9GHz)