CD drive is a ghost :D

Hi a friend of mine recently gave me an old dell GX270 slim he had in his garage after I got tired of my old Toshiba laptop eating hardrives up. There were only two problems with it we needed to upgrade the video card and replace the non functioning cdrom. There is an issue with the AGP video card having a black screen but I will post that issue in the proper part of the forum. We installed a 400w PSU and a Samsung SH-S162L cddrive. When we go into device manager no matter what we do the thing insists the factory cdrom is there and that there is nothing wrong with it despite it sitting unattached and in my hands. The drive will boot up if a disk is inserted or upon booting the computer up it will fire up for a couple seconds but then goes dormant again. why doesn't my computer seem to see the drive no matter how I hook up I tried moving the master/slave/cable select catch around but changed nothing. Why does my computer continue to reinstate the factory cd driver even if I uninstall it and remove the device entirely from the computer? and why does the new drive not function either? Lets say for some retarded reason it won't let me pull the factory cddrive off the machine I should still be able to install the new one as a slave or something right?