Like with any other desktop computer, damage to the Dell Optiplex SX270 can occur over time. If you need to replace a malfunctioning internal component, such as a RAM module or hard drive, you'll need to open up the computer tower.
Turn off your Optiplex and unplug all cables from the back of the computer tower.
Remove all screws from the sides and corners of the rear of the computer tower.
Slide the removable panel off the side of the tower to expose the computer's internal components.
Locate the rectangular hard drive compartment on the inside of the computer tower, near the back. Press the green button on the hard drive cover down. Lift the cover up to expose the hard drive.
Remove the screws from the corners of the hard drive and disconnect the hard drive cable from the port at the end of the hard drive. Set the hard drive aside.
Locate the rectangular memory module connected to the motherboard of the computer.
Pull the metal tabs at the end of the memory module outward. The module automatically pops up. Remove it from the motherboard.