I gonna to write now Organization of a Microcomputer : Hardware Organization Part -6 and last part. So dont wait see this last part of Microcomputer Hardware Organization.
CD-ROM Drives :
A CD-ROM drive is capable of storing over 600MB of data on a single 5-inch disk. CD-ROMs are suitable for distribution of large software packages and can contain all types of multimedia data. The CD-ROM technology is low cost and easy to produce. In future it will be possible to save data or programs on a CD-ROM in real-time, similar to a floppy disk. CD-ROM drives can be installed in the same size drive bays as a 5.25-inch floppy disk drive. The CD-ROM drive interfaces to the microcomputer through one of several port adapters. Often, a SCSI adapter comes with the CD-ROM drives are now capable of being attached to the IDE adapter port. The IDE port adapter standard has recently been extended to support additional IDE posts with CD-ROM attachment capability.
Microcomputer System Unit :
Most of the intelligence and functioning of a PC system resides in the system unit. All external input/output devices are attached to the system unit and upgrade and expansion features are installed in the system unit. The system unit is the heart of the microcomputer figure 4.3 is a they of the inside of a desktop microcomputer system unit. The drive bays accept hard disk drives, floppy disk drives and CD-ROM drive of various physical sizes. The motherboard is installed on the case of the system unit. The processor, cache memory, system DRAM , core logic chip set, integrated adapters and ports, BIOS ROM, and expansion slots are mounted on the motherboard. What is actually in a microcomputer depends on the PCs packaging style and its bus architecture.
