How do I remove the HD from a blue and white G3?

Are you interested in removing the drive before e-cycling the computer or are you replacing the hard drive? I ask because if it won't be used again, you don't need to be concerned about electrostatic discharge that could damage any components on the motherboard while you're working to remove the drive. There were 2 hardware methods used to secure the hard drive(s), depending on when your B&W was manufactured. If your B&W was one of the early models, it will have a full-length, steel carrier that runs from the front to the back of the chassis floor. To access the (4) machine screws that secure the hard drive to the carrier, you need to remove the carrier. After opening the side panel, you'll see the hard drive. You need to disconnect the power supply cable (marked P1) from the motherboard (press the connector's release tab inward and lift it straight up), and then move the wiring harness connected to it out of the way. Disconnect the power and data cables from the hard drive and then locate the screw at the end of the carrier (circled in red, near the back of the computer case), that secures the carrier's clamping plate. Remove the screw and plate and then slide the entire carrier to the back of the computer and lift it up and out of the case. You may have to angle it to clear everything.

If you have the improved version of the B&W, each hard drive is mounted to an individual metal sled that's secured to the chassis floor with a single screw. Disconnect the power and data cables from the drive to locate the screw (circled in red) and remove it. Pull the sled toward the motherboard to disengage it and lift it out of the computer case. Turn it over to remove the (4) hard drive mounting screws.

Note that the hard drive's power connection can be firmly stuck in place. You need to apply strong pressure as you rock it from side to side, to loosen it. If you're e-cycling the computer, you can clamp a pair of pliers on the white connector, to grip it firmly while wiggling/prying it out. If your B&W has the Ultra-SCSI hard drive, you'll notice the long, off-white-colored ribbon cable extending from the SCSI controller card to the hard drive mounted at the front of the computer. The ribbon cable is folded at 45º angles and stuck to the hard drive. Just pull it off to get it out of the way. Good luck.

Information about opening the computer and about internal storage could earlier be found in the setup guide (manuals.info.apple.com/Apple_Support_Area/Manuals/desktops/0340687APWRMACG3SU.PDF), which does not appear to be available for direct download any more.

A web search for something like removing hard drive and the computer model should help, though.

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