Intel Xeon E5 2690 v3 's Advantages
Released 2 years and 6 months late
Higher specification of memory (DDR4-2133 vs DDR3)
Larger L3 cache size (30MB vs 15MB)
More modern manufacturing process (22nm vs 32nm)
Intel Xeon E5 1660 's Advantages
Higher base frequency (3.3GHz vs 2.6GHz)
Lower TDP (130W vs 135W)