Xeon X3440 's Advantages
Lower TDP (95W vs 135W)
Intel Xeon E5 1686 v3 's Advantages
Released 5 years late
Higher specification of memory (2133 vs 1333)
Newer PCIe version (3 vs 2)
Higher base frequency (2.6GHz vs 2.533GHz)
Larger L3 cache size (30MB vs 8MB)
More modern manufacturing process (22nm vs 45nm)