To use DDR Dual Channel configuration in order to achieve the maximum performance your CPU is capable of giving you, you will need a motherboard with this feature and two identical memory modules.

There is one exception, though: the Athlon 64 processor. On this processor family the memory controller is embbeded in the CPU, not in the chipset. Therefore with this CPU the use of DDR Dual Channel configuration depends on the CPU, not on the motherboard. Socket 754 Athlon 64 processors aren't capable of this configuration. So if you have this kind of CPU you can't use DDR Dual Channel. Socket 939 Athlon 64 processors have an embbeded Dual Channel memory controller, thus allowing this processor to use this configuration. The installation steps are the same for other kinds of processors, as we will explain below.

As we said, the motherboard must have this feature – actually, the chipset must have it. There are several chipsets with this feature. For the AMD platform we can mention nVidia nForce 2 and VIA KT880, and for Intel platform we can mention Intel 865, Intel 875, Intel 915, Intel 925, SiS 655 TX, SiS 655 FX, SiS 656, VIA PT880 and VIA PT894, just to name a few.

The instalattion, however, is tricky. You have to install each module on a different channel in order to work. The problem is that usually the modules aren't installed in a sequential order. Usually you need to install the first module on the first socket and the second module on the third socket (not the second, as you may think).

The motherboards manufacturers, in order to facilitate the memory installation, usually uses sockets with different colors for better identifying where you must install the memory modules. Usually you need to install the modules on sockets with the same color. Some manufacturers like MSI do the opposite, you must install the memory modules on sockets with different colors! And there are several motherboard models with DDR Dual Channel support that have all sockets with the same color!

So, the best way to avoid errors is to find sockets 1 and 3 and install the modules there.

We give some examples at random on the next pictures.

Figure 3: Colored sockets on a Gigabyte GA-8IPE1000 Pro 2. Just install the modules on a socket with the same color. If you install one module on a purple socket, install the other on the other purple socket.

Figure 4: Colored sockets on a Soltek SL-75FRN Golden Flame. Just install the modules on the yellow sockets.

Figure 5: Pay attention with MSI. On 865PE Neo2 you should install the modules on sockets with different colors (not same color as it happens with other motherboards).

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Figure 6: Two memory modules correctly installed using DDR Dual Channel configuration (the motherboard is a Chaintech CT-9CJS Zenith).