Xeon EC5509 's Advantages
Higher specification of memory (1066 vs 4)
Larger L3 cache size (8MB vs 1.5MB)
Intel Xeon D 1527 's Advantages
Released 5 years and 9 months late
Newer PCIe version (3 vs 2)
Higher base frequency (2.2GHz vs 2GHz)
More modern manufacturing process (14nm vs 45nm)
Lower TDP (35W vs 85W)