Xeon 6740E 's Advantages
Released 13 years and 4 months late
Higher specification of memory (6400 vs 1333)
Newer PCIe version (5 vs 2)
Higher base frequency (2.4GHz vs 2.133GHz)
Larger L3 cache size (96MB vs 12MB)
More modern manufacturing process (5nm vs 32nm)
Xeon L5639 's Advantages
Lower TDP (60W vs 250W)