Intel Xeon D 1518 's Advantages
Released 5 years late
Higher specification of memory (4 vs 3)
Newer PCIe version (3 vs 2)
More modern manufacturing process (14nm vs 45nm)
Lower TDP (35W vs 80W)
Intel Xeon E5507 's Advantages
Higher base frequency (2.266GHz vs 2.2GHz)
Larger L3 cache size (4MB vs 1.5MB)