on the 780i I do not remember which slots are the primary high speed slots.. thats something you should be able to find in the motherboard manual

As for the settings.. thats a 'by system' setup

More than likely with Corsair they may need to run their max 'warranty' voltage however I can not make that call.. if the sticks are rated for up to 2.1v thats where they most likely need to be.. some have a 2.2v rating, again something you need to find out in the specs

@ 3.6GHz you should be running memory somewhere between 1066 and 1081 5-5-5-15 2T on 2x2GB Corsair


You may or may not find with less number of memory sticks in the system the Vcore may be relaxed.. typically a Q6600 requires between 1.42-1.46v Vcore to run 3.6GHz however with the Nvidia board their implementation of Vdroop or Load Line Calibration is different from other chipsets so I do not know what that will end up set to

The name of the game is "lowest' voltages possible for CPU/NB/MEM on the highest speed, -STABLE- without exceeding TEMPS and max voltage specs

Its trial and error to find those voltages.. although there are typical ranges, there is no set value for every system