Intel socket LGA1155 CPUs have an embedded memory controller, meaning that it is the processor, not the chipset, that defines what memory technologies, as well as the maximum amount of memory you can have. The motherboard, however, may have a limitation as to how much memory can be installed.
The integrated memory controller from socket LGA1155 processors supports DDR3 memories up to 1,333 MHz under dual-channel architecture, but ASUS says the Maximus IV Extreme supports memory up to 2,133 MHz through overclocking.
The ASUS Maximus IV Extreme has four memory sockets, and since DDR3 memory modules can now be found in capacities up to 8 GB, you can have up to 32 GB with this motherboard if you use four 8 GB modules.
The first and third sockets are red, while the second and fourth are black. In order to achieve the maximum performance, you should install two or four memory modules in order to enable dual-channel architecture. When only two modules are used, install them in the red sockets. Otherwise, your computer won’t turn on.
As with other motherboards from ASUS, the Maximus IV Extreme comes with the “MemOK!” feature, which allows you to test the compatibility of the memory modules that are installed. On this motherboard, the “MemOK!” function is enabled through a button called “GO,” which also allows you to load an overclocking preset after the operating system is loaded. You can see this button in Figure 6, to the right of the main power supply connector.