Intel Xeon E5 2640 v3 's Advantages
Released 7 years and 10 months late
Higher specification of memory (DDR4-1866 vs DDR3
Depends on motherboard)
More modern manufacturing process (22nm vs 65nm)
Lower TDP (90W vs 120W)
Xeon X5355 's Advantages
Higher base frequency (2.667GHz vs 2.6GHz)