Intel Xeon D 1520 's Advantages
Released 3 years late
Higher specification of memory (4 vs 3)
Higher base frequency (2.2GHz vs 1.8GHz)
More modern manufacturing process (14nm vs 32nm)
Lower TDP (45W vs 80W)
Intel Xeon E5 2603 's Advantages
Larger L3 cache size (10MB vs 1.5MB)