The PowerBook G4 computer has an internal hard disk drive with a storage capacity of 30, 40, or 60 GB. The drive has fluid dynamic bearings for quieter operation.
The hard disk drive drive uses the extended IDE (integrated drive electronics) interface, which is also referred to as the ATA interface. The implementation of the ATA interface on this computer is a subset of the ATA/ATAPI-4 specification (ANSI NCITS 317-1998 AT Attachment - 4 with Packet Interface Extension). That specification is maintained by the National Committee on Information Technology Standards (NCITS) Technical Committee T13.
The software that supports the internal hard disk is the same as that in previous PowerBook models with internal IDE drives and includes DMA support. For the latest information about that software, see Technote #1098, ATA Device Software Guide Additions and Corrections. The web page for Technote #1098 includes a link to a downloadable copy of ATA Device Software Guide.
To obtain the reference documents listed here, see the reference links at "ATA Devices".