Running a 64-bit Guest Virtual Machine on a 32-bit Host

I was recently asked by a colleague if it was possible to run a 64-bit guest operating system on a 32-bit host. The question was specifically geared towards running Windows 2008 R2, via VMware Player, on Windows XP.

Yes you should definitely be able to run a 64-bit virtual machine on a 32-bit host like Windows XP. There are a couple of caveats, which include:

1. The virtual machine software must support 64-bit guests. That is, VMware Player must support 64-bit guests, which it does. You should use the latest version (3.0 as of this article) to be sure you get support for Windows 2008 R2. See the release notes for more information.
2. The CPU on the machine must support 64-bit instructions. In the case of Intel based CPUs, EMT64.
3. The CPU must support Virtualization Technology. Again, for Intel CPUs this is the VT extensions.
4. VT must be enabled. This is often accomplished via the Bios.

Those are the perquisites for running 64-bit guests, like Windows 2008 R2, on a 32-bit host. You can check if your CPU supports 64-bit instructions and virtualization technology using CPU-Z, or the VMware shared utilities. VMware also provides additional information in this knowledge base article.