NOTE: Industry-wide, it is not

BACKUP drive with an IDE interface in daisy-chain with the hard disk drive. The performance of the IDE hard disk drive will be degraded. On an IDE bus, the data transfer rate is as fast as the transfer rate of the slowest device. The slowest device in this case will be either the CD-ROM or TAPE BACKUP drive. It is recommended to connect your desktop CD-ROM drive as a MASTER in the next available IDE port in your system. Please reference your system’s manual to identify the number of IDE ports in your PC. If not available, you can guide yourself by identifying where in the system your hard disk drive C: is physically connected to. In older style PC’s, normally you’ll find the hard disk drive C: connected to an I\O card. Check to see if there is a second (unused) 40-pin, male IDE connector on that card. On most current PCs, you’ll most likely find the hard disk drive connected directly into the motherboard. Is there another 40-pin IDE connector on the motherboard?

You have the following options:
A) If there is an unused IDE port on the controller card or embedded within the motherboard, connect the CD-ROM DRIVE to that IDE port. This offers two advantages: First, you won’t have to use another slot on the motherboard for an additional IDE card. Second, the secondary IDE connector already available in your system may be an Enhanced IDE port which will definitely provide faster data transfer through the IDE bus.

B) If there is no other IDE port in your system except the one which your hard disk drive is connected to, connect the CD-ROM drive to a soundcard with an IDE port or a Secondary IDE controller card.