Intel Xeon E5 2640 v3 's Advantages
Higher specification of memory (DDR4-1866 vs DDR3)
Higher base frequency (2.6GHz vs 2GHz)
Larger L3 cache size (20MB vs 6MB)
Intel Xeon E3 1278L v4 's Advantages
Released 9 months late
More modern manufacturing process (14nm vs 22nm)
Lower TDP (47W vs 90W)