Raja, can you post your bios settings for the p9x79 pro, im also using 32gb of corsair vengeance 1600 memory, but im having problems getting 4.8ghz stable. Thanks. 4.6 is good tho, 46x100.
If 4.6GHz is stable using the same DRAM frequency it's not really memory settings you need but more likely a boost in CPU Vcore (maybe a small change to VCCSA for increased IO).
-Raja