As mentioned, there are two hard disk drive cages on P183, one on the lower chamber and one on the top chamber. The two cages are fastened to the chassis using thumbscrews and can be completely removed.

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Figure 21: Hard disk drive cages.

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Figure 22: The two cages outside the case.

The two cages are completely different. The top cage holds up to two hard disk drives, and they are installed to the cage using small drawers. You need to use regular screws, but on the good side there are rubber shock absorbers to reduce the noise level produced by the hard drives. If you remove the two drawers completely you can install a 120 mm fan on this cage using metallic clips that comes with P183, however when this fan is installed you cannot install hard drives to the cage. This fan is in addition to the optional fan that you can install in front of the cage, on the front panel. This cage also has a small toolbox, where you can hold screws and other small parts.

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Figure 23: The top cage.

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Figure 24: Toolbox.

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Figure 25: Place for installing optional fan on the front panel.

On the bottom cage the hard drives are installed perpendicularly, and each one is attached to the cage using regular screws. But like the top cage, the bottom cage uses rubber shock absorbers to prevent the natural vibration from the hard disk drives to be transformed into noise. You can also install an optional 120 mm fan on the front case in front of the bottom cage.