Intel Xeon E5 4640 's Advantages
Larger L3 cache size (20MB vs 15MB)
Lower TDP (95W vs 130W)
Intel Xeon E5 2643 v2 's Advantages
Released 1 years and 4 months late
Higher base frequency (3.5GHz vs 2.4GHz)
More modern manufacturing process (22nm vs 32nm)