The 120mb hard drive installed in the PowerBook 150 is unique from other drives previously used in Macintosh computers. Rather than being a SCSI drive, it is an IDE drive. The PowerBook 150 does still support connecting EXTERNAL SCSI devices however.
The drive is rated at <17ms average access time.
Due to the sensitive nature of IDE devices, removal and replacement of the drive for another is not recommended with the exception of service exchange by trained service personnel.
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