The right side panel is fastened to the case using black thumbscrews, but the left side panel uses three regular screws. Antec should have added thumbscrews on this panel as well, as you may want to route cables behind the motherboard tray.

The side panels from this case are very different. They use three layers. The external layers are made of steel and the internal layer is made of plastic. This was done to improve the acoustic insulation from this case, making your PC quieter.

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Figure 11: Side panel.

In Figure 12 we have an overall look from inside P183. The case is divided into two chambers (one for the power supply and lower hard disk drive cage and one for the motherboard, drive bays and upper hard disk drive cage) in order to improve thermal management. The wall that separates the two chambers has holes for you to pass the power supply cables and a sliding plastic mechanism for you to adjust the size of these holes (Figure 13).

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Figure 12: Overall look.

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Figure 13: Lower chamber.

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Figure 14: Adjustable wall.