Before opening the case, unplug the PC to avoid an electrical shock hazard. Exercise caution as there are sharp edges on a PC and its components. Always wear a static electricity discharge strap and attach the lead to the metal frame of the case, when working with your PC's components to avoid damaging your PC. Note that some manufacturers will void your PC's warranty if you open the case.
If you are replacing a CD-ROM, disconnect the controller cable, power connector and audio connection (if present). Remove the retaining screws and remove the drive.
Set the jumper to "Master" or "MA" if the drive will be the first or only drive on a controller. Set the jumper to "Slave" or "SL" if it will be the second drive on a controller.
Insert the new drive into the bay used for the old drive, or select a bay that has a suitable corresponding opening in the case front. Make sure it is right side up (the button should be under the drawer).
Secure the drive in place with the provided screws or rail inserts.
Connect the controller cable to the drive and the motherboard (the second IDE controller is preferable). Make sure that pin #1 of the cable corresponds to pin #1 on the drive and motherboard. If you have two connectors to choose from, use the one at the end.
Connect the power to the drive.
Connect the audio wire (if one is being used) to the drive and to the sound card or motherboard.