Intel Xeon E5 2686 v3 's Advantages
Released 2 years and 6 months late
Higher specification of memory (2133 vs 3)
Larger L3 cache size (45MB vs 10MB)
More modern manufacturing process (22nm vs 32nm)
Lower TDP (120W vs 130W)
Intel Xeon E5 2643 's Advantages
Higher base frequency (3.3GHz vs 2GHz)