Intel Xeon E5 1681 v3 's Advantages
Released 4 years and 6 months late
Higher specification of memory (2133 vs 3)
Newer PCIe version (3 vs 2)
Larger L3 cache size (25MB vs 12MB)
More modern manufacturing process (22nm vs 32nm)
Intel Xeon X5667 's Advantages
Higher base frequency (3.066GHz vs 2.9GHz)
Lower TDP (95W vs 135W)