HP XU700 Devices on the SMBus, Previous Architecture, •Mono microphone input, •Stereo line level output, •High quality pseudo differential CD input

2 System Board

The Input/Output Controller Hub 2 (82801BA)

•High quality pseudo differential CD input

•Mono microphone input

•An analog line-level stereo inputs for LINE IN

•Stereo line level output

•Meets or exceeds Microsoft’s PC’98 and PC’99 audio performance requirements.

The CS4299 introduces a new architecture that is different from the one used with the CS4280-CS4297 pair.

	Previous Architecture			New Architecture
North Bridge
					North Bridge
		PCI Bus	PCI Slots
South Bridge
					South Bridge
		CS4280 digital		Audio controller link
		controller
	Audio controller link				CS4299
		CS4297

Devices on the SMBus

The SMBus is a subset of the I2C bus. It is a two-wired serial bus which runs at a maximum speed of 100 kHz. It is used to monitor some of the hardware functions of the system board (such as voltage levels, temperature, fan speed, memory presence and type), both at system boot and during normal run-time. It is controlled by the SMBus controller located in the ICH2.

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