Intel Xeon E5 2640 's Advantages
Lower TDP (95W vs 130W)
Intel Xeon E5 2687W v2 's Advantages
Released 1 years and 6 months late
Higher base frequency (3.4GHz vs 2.5GHz)
Larger L3 cache size (20MB vs 15MB)
More modern manufacturing process (22nm vs 32nm)