Intel Xeon E5 4603 's Advantages
Larger L3 cache size (10MB vs 1.5MB)
Intel Xeon D 1520 's Advantages
Released 2 years and 10 months late
Higher specification of memory (4 vs 3)
Higher base frequency (2.2GHz vs 2GHz)
More modern manufacturing process (14nm vs 32nm)
Lower TDP (45W vs 95W)