Principled Technologies tested Harpertown and Nehalem servers running various Windows Server operating systems to show the benefits of processer and of operating system improvements on simulated customer workloads. Windows Server 2008 R2 delivers over 37% more capacity on these tests on the same Nehalem-based servers, revealed. The Hyper-V comparison study, involving the SP2 and R2 releases of Windows Server 2008, was was designed to measure the level of Hyper-V R2 virtualization performance improvements using vConsolidate on a combination of Windows Server platforms and Intel CPUs. In this context, the comparison involved Windows Server 2008 Enterprise Edition SP2 and R2 on Intel Xeon E5450 and X5570.
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