Dr. Patrice Calegari, HPC Application Specialist, BULL S.A.S. and Thomas Varlet, HPC Technology Solution Professional from Microsoft just posted a great technical document covering "Dual-Boot and Virtualization with Windows HPC Server 2008 and Linux Bull Advanced Server for Xeon."

The paper has been posted to the Microsoft HPC community portal windowshpc.net. Here's the abstract of a very well written document worth your attention:

"The choice of an operating system (OS) for a high  performance computing (HPC) cluster is a critical decision for IT departments. The goal of this paper is to show that simple techniques are available today to optimize the return on investment by making that choice unnecessary, and keeping the HPC infrastructure versatile and flexible. This paper introduces Hybrid Operating  System Clusters (HOSC). An HOSC is an HPC cluster that can run several OS’s simultaneously. This paper addresses the situation where two OS’s are running simultaneously: Linux  Bull Advanced Server for Xeon and Microsoft® Windows® HPC Server 2008. However, most of the information presented in this paper can apply to 3 or more simultaneous OS’s, possibly from other OS distributions, with slight adaptations. This document gives general concepts as well as detailed setup information. Firstly, technologies necessary to design an HOSC are defined (dual-boot, virtualization, PXE). Secondly, different approaches of HOSC architectures are analyzed and technical recommendations are given with a focus on computing performance and management flexibility. The recommendations are then implemented to determine the best technical choices for designing an HOSC prototype. The installation setup of the prototype and the configuration steps are explained. Finally, basic HOSC administrator operations are listed and ideas for future works
are proposed."