The first step is obviously opening the computer case. For that, unplug your computer from the power grid, just to make sure that nothing wrong will happen.

To open your computer you need to remove the four screws that hold the two side panels of the case. Some cases, however, have one of the panels permanently attached to the case, as it happened with our case. Looking to the rear side of your computer, these screws are the two on the right, as shown in Figure 5, and the two on the left on the same direction (not shown in Figure 5 because unfortunately our case had its other side panel permanently attached to the case).

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Figure 5: Remove these two screws to open the case.

After removing these screws, remove the case side panels. Without the side panel your computer will look like the computer in Figure 6.

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Figure 6: Computer without its side panel.