ASUS M4A79XTD EVO motherboard comes with two x16 PCI Express 2.0 slots, two PCI Express x1 slots and two standard PCI slots. When only one video card is used, the main PCI Express x16 slot (blue) really works at x16, but when two video cards are installed both slots work at x8.

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Figure 4: Slots.

Socket AM3 CPUs support both DDR2 and DDR3 memories, but the kind of memory you can have depends on the kind of motherboard they are installed on, socket AM2+ or socket AM3, respectively. Being a socket AM3 motherboard, ASUS M4A79XTD EVO supports only DDR3 memories. It comes with four memory sockets and in order to achieve the maximum performance possible you need to install two or four memory modules in order to enable the dual channel feature, which doubles the available memory bandwidth. If two modules are used, you need to install them on sockets with the same color. On this motherboard sockets one and two are black and sockets three and four are blue.

The maximum amount of memory you can have is 16 GB (by using four 4 GB modules) and although officially socket AM3 CPUs support up to DDR3-1600/PC3-12800 modules, ASUS M4A79XTD EVO supports up to DDR3-1800 memories through overclocking.

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Figure 5: Memory sockets.