Another thing about dells, some are tagged for certain cd drives. Leave the old one in and just add a new one and see if it helps. Another note is that on some models the restore cd will only run from a dell cd drive. You may have to buy one from dell if your old one goes out and this is the case. We found this out the hard way after trashing the old drive.
Quote: "Actually, the cable itself has 'master' and 'slave' plugs. I'm not 100% on which is which, but I know that if you have the drive set to 'master' and plugged into the 'slave' cable slot, it wont work."
This is correct from my experiance, though only for some hardware. It will work with some cables. Though on these cables, the cable select option won't work (I belive there is no red [pin 1] mark on these type cables). In any case you can always set the jumpers for master/ slave on the drives and put the master at the very end plug and the slave on the middle plug. This should work with both cable types I believe.