After you insert the hard disk drive to a bay, the screw installed on its last hole will be used to lock the drive to the bay thru a plastic latch (see Figure 16). The hard disk drive will be very tight on the bay, but if you want you can add a screw to the last hole on the right side of the drive (Figure 17).

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Figure 16: Hard disk drive installed in a bay.

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Figure 17: Notice that you can add a screw to the last hole.

As for the two 2.5” hard disk drive bays, they are available on the panel that divides the power supply compartment from the motherboard one. As mentioned, this panel can be removed, what helps the installation of 2.5” drives. One bay is available on the top part of the panel and the other is available right below it, upside down.

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Figure 18: Panel with two 2.5” hard disk drive bays.

On Figure 19 you can see a 2.5” hard disk drive installed on the top bay.

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Figure 19: Laptop hard disk drive installed on the top 2.5” bay.