Dell OptiPlex GL Service Manual - Page 9

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. System Overview 1-1