In 2005, Intel, and later AMD, built extensions to their x86 chip architectures that took much of the resource-management load off the hypervisors, making it much easier to build a hypervisor that could run guest operating systems as virtual servers without having to modify them first.

Like Intel, AMD built virtualization-enabling enhancements into its chips that put the responsibility for managing requests from applications, guest operating systems and the hypervisor on the chipset itself. AMD's implementation is called AMD-V which, like Intel's IVT, allows a physical server to support virtualized servers without taking a large performance hit.

More recently, AMD worked with the National Security Agency to try to make virtual systems more secure at the chip level by building in authentication mechanisms to limit what either the server or OS could do. AMD is expected to ship a new generation of chips later this year that will introduce chip-managed trusted hardware to the virtualization market. Intel is expected to introduce a similar capability.

• AMD-V
• Rapid Virtualization Indexing (recent enhancement to allow faster shifting among virtual OSes and improve performance of applications on quad-core processors)