Make sure that the DVD SATA cable is connected.Make sure that the DVD power cable is connected.ExplanationThe first thing to check would be the simple and obvious things. Make sure that the cable connecting the DVD drive is secure. It is possible that during the installation of the hard disk that the cable might have come loose. All of the other choices would involve significantly more work. Master and Slave settings are not used on SATA devices. Moving the DVD drive to another system might make it start working, but you should verify the current configuration before trying that. Replacing the DVD drive should only be done after you verify that it is not working correctly.