Intel Xeon D 1557 's Advantages
Released 6 years late
Newer PCIe version (3 vs 2)
More modern manufacturing process (14nm vs 32nm)
Lower TDP (45W vs 130W)
Intel Xeon X5680 's Advantages
Higher specification of memory (DDR3 vs DDR3)
Higher base frequency (3.333GHz vs 1.5GHz)
Larger L3 cache size (12MB vs 1.5MB)