AFAIK, that is how you should set up if you opt for Cable Select.
But did you connect the drives jumpers correctly?
In a CD-ROM + DVD-ROM combination you could try attaching the CD-ROM to the end connector and the DVD-ROM to the mid-connector with both set to Cable Select.
See if this works.
Personally I have stuck with the Master/Slave set up all this while and have never changed.
I'm not sure if this is a Win XP problem or a hardware problem. My computer has two harddrives and two optical devices (CD-Rom and DVD.) When I setup the computer, I couldn't get it to recognize the harddrives correctly unless I set them in the Cable Select position. Having solved that problem, I next tried to set my optical devises to Cable Select. I read somewhere that if you use Cable Select on the primary IDE, you should also use it on the secondary IDE. However, I couldn't get the system to see both optical devices unless I reverted to the old Master/Slave position.
So, what's the story on Cable Select and Master/Slave?

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