Intel I/O Controller Hub
The Intel I/O Controller Hub line is a popular family of products that combine several I/O devices into a single chipset, which reduces the cost of designing and manufacturing modern PCs. They typically include Power Management, a Network Adapter, Storage Controllers, USB Controllers, an SMBus Controller, an Audio Device and a Modem Device.
http://www.intel.com/design/chipsets/datashts/290655.htm - Intel ICH0 Datasheet (This version is used by VirtualBox)
http://www.intel.com/content/www/us/en/chipsets/82801db-io-controller-hub-4-datasheet.html - Intel ICH4 Datasheet