For what its worth, if anyone's curious, one day I actually pulled the adapter board off the back of the DVD drive on my slot load iMac. Between the adapter board and the drive is a standard laptop ATAPI connector, the same as most other iMacs and laptops. I have actually run a standard notebook drive on it, too, which means that the iMac is electrically compatible with standard drives. However, its not physically compatible. The connector is on the complete opposite side to what it is on a standard drive, meaning that while it will physically connect, you won't be able to mount the drive, you'll have to have it sitting on top of the iMac which you'll have to have sitting upside down. I did this to get Tiger installed on my iMac, since for whatever reason the iMac DVD drive didn't like my Tiger DVD, but its not something you'd really want to do unless you really, really, really have to.