As use of Intel Virtualization Technology for IA-32 and Intel 64 Architectures (Intel VT-x) has grown, the demand for improved performance in virtualized systems has increased. The Intel microarchitecture code name Nehalem and Intel microarchitecture code name Westmere, have introduced extensions to Intel VT-x and its underlying hardware support to meet these increasing performance demands. This paper discusses the architectural and microarchitectural improvements provided by these processors and how they translate into improved performance for software that uses this technology.