Updating Imported Parallels VMs to Support 2-way SMP and Power Management

Updating Imported Parallels VMs to Support 2-way SMP and Power Management

Disclaimer: This is a personal document and is not official or endorsed by VMware. Feedback, suggestions, and edits are welcome.

Some users have imported their Parallels or Virtual PC for Mac VMs to VMware Fusion and are bummed to find they can't enable multiple virtual processors or power management.

This is because Parallels VMs running Windows are built using a non-ACPI HAL that does not support these two features, and because converting a VM from Parallels to Fusion does not change the HAL due to Windows constraints, converted VMs cannot use VMware Fusion's support for dual virtual CPUs or power management.

The solution is to change the HAL. Before Windows XP, it was fairly easy: just go into Device Manager and choose a new one (NT4) or delete the old one and reboot (2000). Unfortunately, Microsoft does not support changing an XP VM's HAL without reinstalling Windows.

A lot of people asked, "Okay, how do you do that?" So Brian Rice prepared this followup. If you follow it, be sure to make a backup before you start! The following is Brian's experience, not an official VMware document. Frankly, most of what's in this document is Microsoft stuff rather than VMware stuff anyway.

See Brian's writeup below:

Start off with a Parallels VM and converted it to VMware Fusion using VMware Fusion 2's built in import function.

Next connect Windows XP SP2 CD to the imported Virtual Machine. When Windows notices the CD, it runs the CD's autoplay script and gives this menu:

Pick "Install Windows", choose


from the "Installation Type" pulldown. NOTE: You will have to re-enter your Windows product key. Pretty soon, Windows reboots into its text (non-GUI) installer.

WARNING! If you're following along, be alert here!

When Windows reboots, click once in the window to ensure that it has input focus. Windows will, for a few seconds, display a message telling you to press F6 if you have a driver disk.


, when you see that message, press F5.

Windows will not acknowledge the fact that you pressed F5 right away. But in a few seconds, it will show you this screen:

Believe it or not, that's a scrolling window. Use the up-arrow to scroll all the way up to

ACPI Multiprocessor HAL


ACPI Uniprocessor HAL


Either of these HALs will allow your VM to shut down cleanly, without requiring the

gui.exitonCLIHLT = "TRUE"

.vmx file hack that that PDF discusses. But only

ACPI Multiprocessor HAL

will allow your VM to have two virtual CPUs. So I picked

ACPI Multiprocessor HAL

and let the reinstallation proceed.

Eventually Windows rebooted into its GUI installer, and the boring part began.

After 30 minutes or so, Windows finishes reinstalling itself; you can choose to decline the opportunity to register my copy of Windows again; and then your VM is back. Just one catch: the mouse was a little broken. Apparently, something in the reinstall process messes up the VMware mouse driver. To resolve this issue, ctrl-cmd to get input focus out of the VM, and then re-launch the VMware Tools installation once again (as always, by pulling down the

Virtual Machine

menu and choosing

Install VMware Tools


But this time do a


of VMware Tools rather than an



Allow VMware Tools to reboot the VM as always, and the mouse should be back to normal on reboot. To enable multiple virtual processors or power management, you need to shut down the VM.


Stand By

isn't grayed out anymore! That's because we now have an ACPI HAL.

While the VM was powered off, go to VMware Fusion's


dialogue and changed the number of virtual CPUs from 1 to 2. Power on your imported VM and revel in the multiprocessor goodness.

Now your imported Parallels or VPC virtual machine will support the same features as a newly created VMware Fusion virtual machine with regards to SMP and Power Management.

Version history
Revision #:
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Last update:
‎08-16-2008 05:46 PM
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