Intel Xeon E5 1691 v3 's Advantages
Released 3 years and 5 months late
Higher specification of memory (2133 vs 1333)
Larger L3 cache size (35MB vs 24MB)
More modern manufacturing process (22nm vs 32nm)
Xeon E7 8837 's Advantages
Higher base frequency (2.667GHz vs 2.5GHz)
Lower TDP (130W vs 135W)