Intel Xeon E3 1220L 's Advantages
Higher base frequency (2.2GHz vs 1.7GHz)
Larger L3 cache size (3MB vs 1.5MB)
Lower TDP (20W vs 65W)
Intel Xeon D 1587 's Advantages
Released 4 years and 10 months late
Higher specification of memory (DDR3 vs DDR3)
More modern manufacturing process (14nm vs 32nm)