The Dell C521 desktop computer was the first from the company to use AMD desktop processor. When released in 2006, many considered the 320 GB hard drive that shipped with the unit humongous, which was true at that time. However, these days, high-quality audio and video files can quickly consume that amount of space. With 2-terabyte drives available for under £65, replacing the hard in the C521 is a smart upgrade. Before you can upgrade the drive, though, you must remove the current drive.
Connect a USB flash drive or external hard drive to the C521 computer. Back up all of your important files to the external storage device. Disconnect the USB flash drive or external hard drive from the computer.
Shut down the Dimension C521 computer. Disconnect the power plug and cables as well as all other peripherals from the computer. Place the computer on a sturdy table or other flat work surface.
Loosen and remove the two retaining screws on the rear of the C521 that secure the access panel on the right side of the case enclosure. Remove the access panel from the case. Remove the screws for the left-side access panel. Remove the left side panel from the case.
Clip the metal end of the antistatic wrist strap to the metal interior the computer case. Slide the wrist strap over your arm. Touch the metal inside the case to discharge any static electricity in your body.
Disconnect the ribbon cable and power connector cable from the hard drive. Use the Phillips screwdriver to remove the two screws on either side (four screws in all) of the hard drive that secure it in the mounting bay.
Slide the hard drive out of the rear of the mounting bay.
Install the new hard drive by reversing the steps used to remove the old one. Close the case and reconnect all the cables. Reinstall the operating system on the computer.