Intel  I/O Controller Hub 9 (ICH9) Family
Intel  82801IB ICH9, 82801IR ICH9R, 82801IH ICH9DH, 82801IO ICH9DO, 82801IBM ICH9M and 82801IEM ICH9M-E,and ICH9M-SFF ICH9-I/O Controller Hubs

Overview
The ICH9 provides extensive I/O support. Functions and capabilities include:
* PCI Express* Base Specification, Revision 1.1 support
* PCI Local Bus Specification, Revision 2.3 support for 33 MHz PCI operations (supports up to four Req/Gnt pairs).
* ACPI Power Management Logic Support, Revision 3.0b
* Enhanced DMA controller, interrupt controller, and timer functions
* Integrated Serial ATA host controllers with independent DMA operation on up to six ports (Desktop only) or four ports (Mobile only) and AHCI support.
* USB host interface with support for up to twelve USB ports; six UHCI host controllers; two EHCI high-speed USB 2.0 Host controllers
* Integrated 10/100/1000 Gigabit Ethernet MAC with System Defense
* System Management Bus (SMBus) Specification, Version 2.0 with additional 2 support for I C devices
* Supports Intel  High Definition Audio
* Supports Intel  Matrix Storage Technology (Intel  ICH9R, ICH9DH, ICH9DO, ICH9M, and ICH9M-E Only)
* Supports Intel  Active Management Technology (Digital Office only)
* Supports Intel Virtualization Technology for Directed I/O
* Supports Intel  Trusted Execution Technology
* Low Pin Count (LPC) interface
* Firmware Hub (FWH) interface support
* Serial Peripheral Interface (SPI) support
*Intel  Quiet System Technology (Desktop Only)
* Integrated TPM 1.2 (Mobile Only)
The Intel ICH9 incorporates a variety of PCI devices and functions, as shown in Table 1-3. They are divided into seven logical devices. The first is the DMI-To-PCI bridge (Device 30). The second device (Device 31) contains most of the standard PCI functions that always existed in the PCI-to-ISA bridges (South Bridges), such as the Intel PIIX4. The third and fourth (Device 29 and Device 26) are the USB host controller devices. The fifth (Device 28) is PCI Express device. The sixth (Device 27) is the HD Audio controller device, and the seventh (Device 25) is the Gigabit Ethernet controller device.