Apple twentieth anniversary mac Service Manual

m 2 MB of built-in video memory using synchronous graphic RAM (SGRAM)

m 4 MB of read-only memory (ROM)

m 50 MHz High Performance Module (256K level 2 cache)

Internal storage devices

The following storage devices were installed in your computer at the factory:

m Apple SuperDrive 1.4 MB high-density floppy disk drive 

m 2 gigabyte (GB) Apple ATA (Advanced Technology Attachment) hard disk drive, also known as an

Enhanced Integrated Device Electronics (IDE) hard disk drive

m a custom front-loading CD-ROM drive

CD-ROM drive specifications

Disc diameter

m 120 millimeters (mm) (4.7 inches)

m 80 mm (3.2 inches)

Average access time

m

Audio:  380 milliseconds (ms) for playing audio CDs

m Data:  200 ms

Data capacity

m 656 megabytes (MB), Mode 1 

m 748 MB, Mode 2

Maximum playing time

m 74 minutes, 42 seconds

Technical

Information   

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