The quad-channel architecture quadruples the available memory bandwidth. This is done by expanding the memory data bus to 256 bits, which is accomplished by accessing four memory modules at the same time.
Currently, this mode is available only on the Intel socket LGA2011 (LGA2011) platform. This means that you can only enable this mode on motherboards and Core i7 CPUs that use this socket. These processors support DDR3 memories up to 2,133 MHz.
You will need four identical memory modules. Eight modules can be used on motherboards with eight memory sockets, and each group of four modules can have different capacities, but the modules inside the same group must be identical. If you install two or three memory modules, they will be accessed in dual- or triple-channel mode, respectively. Of course, in this case, you won’t achieve the maximum performance of which your system is capable.
There are two kinds of socket LGA2011 motherboards available: those with four memory sockets and those with eight or more memory sockets.
On motherboards with four memory sockets, simply fill all the sockets that are available.
Motherboards with eight memory sockets use the traditional scheme utilized by motherboards targeted to Intel CPUs. You must install the memory modules in the first, third, fifth, and seventh memory sockets, and these sockets almost always will use the same color, while sockets two, four, six, and eight will use a different color. Therefore, simply install the memory modules in sockets with the same color. On socket LGA2011 motherboards, usually half the sockets are at one side of the CPU socket, while the other half is on the other side. See Figures 13 and 14.
If you want to install eight memory modules, the second group of memory modules must be installed in sockets two, four, six, and eight unless all eight modules are identical, in which case you will fill all eight memory sockets and won’t need to worry about which sockets to use.