Since running VMware Workstation 5.5 on my Vista PC with a duo core CPU, I always get this message "Your host's BIOS does not have valid NUMA information" whenever I start a virtual machine and my host system is blocked for some minutes. The message also refers to two knowledge base articles (document ID 938 and 1236). Since I know that many of my readers are moving to Vista with duo core CPUs these days, I will post the solution to the problem here.

NUMAThe knowledge base article actually describing this solution has the doc id 2039, although, it doesn't mention Vista. VMware Workstation seems to be having problems sometimes on machines with multiple CPUs. I didn't experience this with Windows Server 2003. However, it might also be related to the fact that I am running Vista on a machine with different hardware. The reference to NUMA (Non-Uniform Memory Architecture) in the error message is a hint that this problem is related to AMD CPUs. However, you can't often trust these messages.

The recommended configuration settings in the knowledge base article also improves the performance, especially, during the VM's boot-up process. It will then only run on one CPU core, which has the advantage of your host being able to use the other core. When I ran VMware Workstation on a machine with only one CPU core, my host was often quite sluggish whenever one of the VMs is busy.

Add host.TSC.noForceSync = TRUE to C: \ProgramData\VMware Workstation\config.ini.

The knowledge base article mentions the Application Data folder under Documents and Settings\All Users. However, "Documents and Settings" doesn't exist anymore in Vista. Please read the article for more information about the meaning of this setting.

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Add processor1.use = FALSE to the vmx file of the virtual machine.

This tells the VM to run on only one CPU core.

  1. A Widdie 15 years ago

    Should this configuration also work on Windows XP with a duo CPU? Thanks

  2. I think these VMware settings should work on all Windows versions. I didn’t try it on Windows XP, though.

  3. Daniel Mason 15 years ago

    Hey! It works on XP with AMD64bit CPU’s

  4. Jawwad 15 years ago

    It worked for me too on the following configuration:
    – Lenovo ThinkPad T60
    – Core duo
    – Windows XP Professional

  5. Kris 14 years ago

    Add processor1.use = FALSE to the vmx file of the virtual machine.

    This tells the VM to run on only one CPU core.

    This worked for my XP with VMware Workstation 5.5.1 build-19175.


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