Now that you have prepated the case, you can install the CPU, the CPU cooler and the memory modules on the motherboard. Of course you can do that later, but since the motherboard isn't inside the case yet is easier to install these components right now.

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Figure 13: Processor, cooler and memory modules installed on the motherboard.

Put the motherboard next to the place where it will be installed in the case, as shown on Figure 14. Don't install it to the case yet. We will use this position to install all the wires and cables that come from the case to the motherboard. You could do this later, but since the motherboard isn't inside the case yet it is easier to do that right now.

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Figure 14: Positioning the motherboard for installing the system cables.