Quoting from the AMD official annoucement:
AMD today announced the broad availability of its I/O virtualization technology specification. Demonstrating continued leadership in evolving the industry-standard x86 processor architecture, AMD is making this technology available through royalty-free licenses that are designed to encourage its widespread adoption by hardware and software developers. By defining a set of technologies that can be directly built into a computer’s I/O bridges, AMD’s I/O virtualization technology is designed to extend the benefits of CPU-assisted virtualization by addressing the performance bottlenecks and security issues that can be encountered when virtualizing I/O devices in x86-based servers, desktops, and notebook computers.
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AMD’s I/O virtualization technology is expected to be supported by all AMD processors in mid-2006, and is also anticipated to be implemented in chipsets and core logic designed for AMD64-based platforms in 2006. The AMD I/O virtualization technology specification download, together with technology overviews and guidance to software developers who are designing virtualization solutions for 64-bit technology, can be found at http://developer.amd.com.