Dells are known for having parts short out, which is why I strongly recommend that anyone who has a Dell machine keep up-to-date with their warranty extensions. If you have a warranty, then get the CD-ROM drive replaced, as it sounds like you've tried everything from a user point of view.
The only other things I can think of trying is upgrading the firmware. Still, it should be recognized.
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It's most likely a problem with your flux capacitor.