Based on my progress with Windows XP under Parallels Workstation, I deciced to fire up the latest Vista bits to see if they would install into the VM. My experiment quickly came to a grinding halt since Parallels doesn’t support ACPI bios under emulation.

According to this thread up on the Parallels support forum, the next version is supposed to have ACPI bios. It’s unclear at this time if that’s the next beta, or the next full release of the product.

Bummer. For now, XP works great, but you won’t be using Vista under VM.