Opteron 13KS EE 's Advantages
Higher specification of memory (1333 vs 3)
Lower TDP (50W vs 80W)
Intel Xeon E3 1220 's Advantages
Released 2 years late
Newer PCIe version (3 vs 2)
Higher base frequency (3.1GHz vs 2GHz)
Larger L3 cache size (8MB vs 6MB)
More modern manufacturing process (32nm vs 45nm)