Intel Xeon E5 2665 's Advantages
Higher base frequency (2.4GHz vs 1.8GHz)
Larger L3 cache size (20MB vs 6MB)
Intel Xeon E3 1258L v4 's Advantages
Released 3 years and 3 months late
More modern manufacturing process (14nm vs 32nm)
Lower TDP (47W vs 115W)