Apple Mac Performa 5300CD - Manual (Page 111)

Opening the computer
1 Shut down your computer by pressing the Power key on the keyboard.
You can also choose Shut Down from the Special menu or the
Apple (K) menu.
2 Turn the computer completely off by pressing the power switch at the back of
the computer.
Press the side of the switch marked with the j symbol.
3 Unplug the cable that connects your keyboard to the computer.
4 Remove the security screws on either side of the computer’s back panel with a
screwdriver.
Remove both security screws.
101 Installing an Expansion Card