Follow the instructions in the link below and see if it fixes the issue.:
Since DVD drives like to be set to "master", how did you set the jumpers?
Hope this helps.
Have a Dell Dimension 4550 with XP. DVD and CD drives started to act up. Replaced both units with new LG DVD writable units. Can't get new drive units to show on "My Computer". Both units have power since trays open and close. Any suggestions as to cause. Have also tried swapping connection cable from board to drives from a sister unit that is working OK. Everything else works fine with machine.