Chapter 1: Introduction 1-2 Chipset Overview The Intel Q35 Chipset is specially designed for use with Intel Core 2 Duo and Quad processors. It consists of two primary components: the Graphic Memory Control- ler Hub (GMCH) and the I/O Controller Hub (ICH9DO). The GMCH manages the data flow between the CPU interface, the System Memory interface, the External Graphics interface, and the I/O Controller through the DMI (Direct Media) Interface. The ICH9DO provides a multitude of I/O related functions. Graphic Memory Controller Hub (GMCH) Utilizing a single LGA 775 socket processor, the Q35 GMCH supports an FSB frequency of 1333/1066/800 MHz.
Host-initiated I/O cycles are decoded to the PCI- Express, the DMI, or the GMCH configuration space. Host-initiated memory cycles are decoded to PCI-Express, DMI or system memory. The GMCH supports 36-bit host bus addressing and a Cache Line Size of 64 bytes. The GMCH supports one or two channels of DDR2 memory with up to two DIMMs per channel with a maximum bandwidth of 6.4 GB/s in asymmetric mode or 12.8 GB/s in symmetric mode using DDR2 800 MHz memory. It also supports an op- portunistic refresh scheme, a memory thermal management scheme and Partial Writes to Memory using Data Mask (DM) signals.
The GMCH contains one PCI-Express x16 port intended for an external PCI-Express graphics card that is compatible with the PCI Express Base Specification revision 1.1. This PCI-E x16 port runs at a frequency of 2.5 GB/s on each lane and supports a maximum theoretical bandwidth of 40 GB/s in each direction for an aggregate of 8 GB/s @ x16. It supports traditional PCI-/AGP-style traffic and a PCI-Exp. Enhanced Addressing Mechanism with advanced capabilities in automatic discovery, negotia- tion and training of link out of reset. Providing the high-speed, chip-to-chip connection between the GMCH and ICH9 is the Direct Media Interface (DMI).
The DMI integrates advanced priority-based servicing, allowing for concurrent traffic, true isochronous transfer capabilities and permitting current as well as legacy software to function seamlessly. Intel ICH9DO System Features The Intel 9th Generation I/O Controller Hub (ICH9DO) supports a variety of I/O related functions and PCI devices, including the following: DMI-to PCI Bridge LPC Controller SATA Controllers #1 and #2 Thermal Subsystem SMBus Controller USB FS/LS UHCI Controllers #1, #2 Note: For more information on the ICH9DO, please refer to Intel's website. 1-9