Usually, most motherboards can only handle two IDE devices per controller. Commonly, there are two IDE controllers...usually one that's dedicated to CD-ROM drives and the other dedicated to Hard Drives.
So, I think you can only have a master and slave device on each IDE controller.
To hook up more than two drives, then you'd need to plug the third drive and slave it on the second IDE controller (usually the one with the CD-ROM drive connected to it).
|Desktop PC| |Macbook Air 13" (Mid 2013)|
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