Chapter 1 System Overview - Dell Dimension XPS H266 Service Manual

Chapter 1
System Overview
T
®
he Dell Dimension
single-processor computer systems that use an Intel
processor with MMX ™
expansion bus as well as a high-performance PCI local bus. These buses are
built into the system board, which also integrates all other elements of the basic
computer system.
The Dell Dimension XPS H233 and XPS H266 systems are available in either a
desktop or a mini tower configuration. Both configurations use the same system
board and base chassis. The only difference, other than physical mounting, is
the number of externally-accessible 3.5-inch drive bays.
The Dell Dimension XPS H233 system operates at an internal frequency of
233 MHz and an external frequency of 66 MHz. The Dell Dimension XPS
H266 system operates at an internal frequency of 266 MHz and an external fre-
quency of 66 MHz. A single-edge contact (SEC) cartridge connected to the
system board contains the system's microprocessor and cache circuitry.
Main memory consists of two or four EDO SIMMs arranged in pairs. The base
configuration for main memory is two 16-MB nonparity SIMMs. Main memory
can be expanded up to 128 MB using 16- or 32-MB SIMMs.
The front of the computer has two 5.25-inch drive bays, one (desktop system) or
two (mini tower system) 3.5-inch drive bay(s), plus a 3.5-inch diskette-drive
bay. The 5.25-inch and 3.5-inch drive bays can hold diskette drives, tape drives,
or CD-ROM drives.
XPS H233 and XPS H266 systems are high-speed,
technology. These Dell
® ®
Pentium II micro-
®
systems incorporate an ISA
System Overview 1-1