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Figure 6: Opening Sonata Plus 550.

The thumbscrews used on this case are very different from traditional thumb screws: after you unscrew them from the case they stay stuck on the side panel, so it is impossible to lose them, as shown on Figure 7.

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Figure 7: The thumbscrews stay stuck to the side panel.

The side panels are protected internally with a plastic layer. According to Antec this layer was added to reduce the noise level produced by the PC.

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Figure 8: The side panels have a plastic layer on their inner side.

Even though on this case you can remove both side panels, the motherboard tray is hard-bolted to the case. This is the strongest disadvantage from this case. Even though it is not difficult to install a motherboard to this case, we like removable trays because they facilitate not only the installation of the motherboard to the case, but also the addition of small components like memories and the CPU to the motherboard. On Figure 9 we show this problem, with the red arrows show the location of the bolts.

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Figure 9: The motherboard tray is permanently attached to the chassis.