I have an Asus P7P55-M motherboard with core i5-750 and 2 x 2gb DDR3 Corsair xms3 ram modules rated at 1333Mhz. The motherboard has four slots and is dual channel. At the moment I have the two ram modules in the light blue slots. As I understand it, this means the two modules are on different channels, and this gives best performance, is that correct? I ask because I have just bought a 4GB single module as they are so crazy cheap at the moment (£14.99 delivered from amazon, already gone up to £19!) If I leave the two old modules where they are and fit the 4GB module in one of the black slots, will that mean that 6GB of ram is on one channel and only 2GB on the other? So I should move one of the 2GB modules into a black slot, and the 4GB into the now empty blue slot. Im aware the difference is not great, but I may aswell get it right as I dont upgrade too often.