Chapter 1
System Overview
This service manual covers the Dell®OptiPlex ®GXpro high-speed, upgrad- able desktop systems, which use the Intel®Pentium®Pro family of microprocessors. These Dell systems incorporate the high-performance PCI local bus as well as the ISA expansion bus. These buses are built into the system board, which also integrates a 3.3-V Pentium Pro microprocessor and all other elements of the basic computer system.
The Pentium Pro microprocessor contains a built-in clock multiplier circuit, which increases the microprocessor’s internal operating frequency to a multiple of the system clock frequency. The microprocessors for each of these systems and their operating frequencies are as follows:
•Dell OptiPlex GXpro 180 systems — 180 MHz derived from a system clock frequency of 60 MHz
•Dell OptiPlex GXpro 200 systems — 200 MHz derived from a system clock frequency of 66 MHz
Dell OptiPlex GXpro systems contain either an integrated 10-Mbps or 10/100-Mbps 3Com® NIC, both of which are covered in this document.
