VMWare asynchronous TSCs on Opteron

A rare VMWare error message is this one, occuring when the virtual machine is being launched:
Your host does not have synchronized TSCs. Please read VMware Knowledge Base article 2041.

Your host does not have synchronized TSCs. Please read VMware Knowledge Base article 2041.

When that error message pops up it is likely that all sorts of time-related things will go wrong in the guest system: Video playback, audio for the video, double-clicks.

An example environment where this can occur:

  • Host system Windows XP
  • CPU AMD Opteron for socket 939 (175, 180, 185, 190)
  • Certain drivers, such as those installed by MSI Live Monitor (AMD CPU Driver 1.3.2.16?)

Fix

I fixed the problem by adding these lines on the bottom of the .vmx file:

processor0.use = TRUE
processor1.use = FALSE
host.noTSC = "TRUE"
ptsc.noTSC = "TRUE"
host.TSC.noForceSync = "TRUE"

That way the guest system only has a single core CPU and only one core of the Opteron helps to emulate it, but that seems to be the only disadvantage.

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