Intel Xeon E5 2666 v3 's Advantages
Released 6 months late
Higher specification of memory (DDR4-2133 vs DDR3-1600)
Larger L3 cache size (25MB vs 8MB)
Intel Xeon E3 1226 v3 's Advantages
Higher base frequency (3.3GHz vs 2.9GHz)
Lower TDP (84W vs 135W)