Dell OptiPlex Gn+, Руководство по обслуживанию

Страница: 23 / 139

System Overview 1-11
Low-Profile Computers
The hard-disk drive assembly (consisting of the hard-disk drive and the hard-
disk drive bracket) is located inside the chassis at the left front of the computer
and is attached to the bottom of the chassis. One EIDE 1-inch-high hard-disk
drive can be mounted on the hard-disk drive bracket.
Midsize Computers
The hard-disk drive bracket is located next to the externally accessible drive
bays at the front of the computer. The hard-disk drive bracket can contain either
one or two 1-inch-high EIDE hard-disk drives, or one 1-inch-high EIDE hard-
disk drive and one 1.6-inch-high EIDE hard-disk drive.
Mini Tower Computers
The hard-disk drive bracket is located beneath the externally accessible drive
bays at the front of the computer. The hard-disk drive bracket can contain either
one or two 1-inch-high EIDE hard-disk drives, or one 1-inch-high EIDE hard-
disk drive and one 1.6-inch-high EIDE hard-disk drive.
Enhanced Dual-Interface EIDE Subsystem
The EIDE subsystem provides two mode-4, DMA bus-mastered EIDE inter-
faces, each of which can support up to two EIDE devices. The EIDE controller
attaches to the high-speed PCI local bus.
The primary EIDE interface (IDE1) supports up to two high-performance EIDE
devices. The computer’s boot drive should be connected to this connection (the
primary EIDE interface).
The secondary EIDE interface (IDE2) also supports up to two high-
performance EIDE devices, typically EIDE tape drives or CD-ROM drives.
NOTE: The externally accessible drive bays at the front of the computer are
normally used for diskette drives, CD-ROM drives, and/or tape drives. Hard-
disk drives should be installed in the internal hard-disk drive positions
described in “Hard-Disk Drive Options” found earlier in this chapter. For
detailed information about the data storage subsystem, see Chapter 7, “Install-
ing Drives,” in the Reference and Installation Guide.
Built-In Video Controller
The video subsystem consists of a high-speed, high-resolution S3 Trio
64V2 86C785 video controller built into the system board. Because the video
controller connects to the PCI bus rather than to the ISA bus, communication
between the video subsystem and the microprocessor is much faster. The PCI
bus operates at a frequency of 33 MHz as opposed to the 8.25-MHz operating
frequency of the ISA bus.
The built-in video controller includes 2 MB of video memory built into the sys-
tem board.