Opteron 3320 EE 's Advantages
Lower TDP (25W vs 80W)
Xeon E 2456 's Advantages
Released 11 years late
Higher specification of memory (4800 vs 3)
Newer PCIe version (5 vs 2)
Higher base frequency (3.3GHz vs 1.9GHz)
Larger L3 cache size (18MB vs 8MB)
More modern manufacturing process (10nm vs 32nm)