How to Open a G5 Tower Case
The Apple Macintosh G5 was the last of the PowerPC models the company released before it switched its processors to Intel. Apple used the same outer casing for the Mac Pro, but removed the massive cooling system because it was no longer necessary. The Mac Pro and the G5 tower are virtually indistinguishable from each other on the outside.
Unplug everything from your Apple Macintosh G5 tower computer; disconnect it from the electrical outlet; remove any peripherals such as hard drives, optical drives, printers, scanners; and unplug the monitor, mouse and keyboard.
Move the G5 tower to a flat, strong, uncluttered work surface. Put a soft towel down to prevent scratches to the surface and computer.
Touch the metal of the G5 tower with a screwdriver blade to release any built-up static electricity. Touch your hand to a metal surface to release any static electrical charge that you carry. This will protect you from getting a shock, and prevent electrical damage to the G5 tower.
Pull up the latch with the padlock label on the back of the G5 tower -- you'll find it on the left side as you view the back. This releases the side of the G5 tower so you can remove the case.
Pull the side panel -- virtually the entire side of the G5 tower -- away from the top of the computer. Set the panel away from your work area.