Intel Xeon D 1587 's Advantages
Released 5 years and 11 months late
Higher specification of memory (4 vs 3)
Newer PCIe version (3 vs 2)
More modern manufacturing process (14nm vs 32nm)
Intel Xeon L5609 's Advantages
Higher base frequency (1.866GHz vs 1.7GHz)
Larger L3 cache size (12MB vs 1.5MB)
Lower TDP (40W vs 65W)