Xeon E7 2830 's Advantages
Higher base frequency (2.133GHz vs 2GHz)
Larger L3 cache size (24MB vs 20MB)
Lower TDP (105W vs 115W)
Intel Xeon E7 4809 v3 's Advantages
Released 4 years and 2 months late
Higher specification of memory (1866 vs 1333)
More modern manufacturing process (22nm vs 32nm)