Intel Xeon E3 1280 v2 's Advantages
Higher base frequency (3.6GHz vs 2.8GHz)
Intel Xeon E3 1515M v5 's Advantages
Released 3 years and 8 months late
Higher specification of memory (2133 vs 3)
More modern manufacturing process (14nm vs 22nm)
Lower TDP (45W vs 69W)