Intel Xeon E5645 's Advantages
Higher base frequency (2.4GHz vs 2.3GHz)
Larger L3 cache size (12MB vs 8MB)
Intel Xeon E3 1220L v2 's Advantages
Released 2 years and 2 months late
Newer PCIe version (3 vs 2)
More modern manufacturing process (22nm vs 32nm)
Lower TDP (17W vs 80W)