Intel Xeon E5 2420 's Advantages
Larger L3 cache size (15MB vs 1.5MB)
Intel Xeon D 1518 's Advantages
Released 2 years and 10 months late
Higher specification of memory (DDR3 vs DDR3)
Higher base frequency (2.2GHz vs 1.9GHz)
More modern manufacturing process (14nm vs 32nm)
Lower TDP (35W vs 95W)