ACPI Uniprocessor PC option not available in Win2003

[register]

I converted a physical win2003 server into an ESX 3.02 vm. Like others I have converted before it, it was a 2 CPU box. I selected 1 CPU when I edited the memory & CPU settings on ESX.

I have done a few others where I had to change the HAL from Multiprocessor to Uniprocessor. In hindsight, I think those other servers have been win2000. win2003 does not give me the option to select Uniprocessor. So far, I'm not seeing the high host CPU utilization I saw with the win2000 guests.

Does anyone know more about this? Do I need to switch the HAL in a win2003 vm when I go from 2 -> 1 cpu? If so, how can this be done?

thanks

[Dave_Mishchenko · Accepted solution]

The process is described in this thread - http://communities.vmware.com/thread/29415. If you're running SP1 it may be that you just need this hotfix - http://support.microsoft.com/default.aspx/kb/923425.

[kucharski]

Yes, it is recommend to change the HAL when you downgrade processors. Under Windows 2003 it should be UniProcessor. Can you list the options you have when you try changing the HAL.

Thanks...

Michael

[register]

My options are:

ACPI Multiprocessor PC

Advanced Configuration and Power Interface (ACPI) PC

MPS Multiprocessor PC

Standard PC

[kucharski]

For Windows 2003 virtual machines, single processor you want to select

Advanced Configuration and Power Interface (ACPI) PC

Michael

[christianZ]

Watch out - as Dave said you need this patch or SP2. W/O it it is not supported and you can get not predictable results (like myself).

[B_Lee337]

I have been reading about this and I am hoping I am understanding correctly. Hope someone can clarify if I am correct in the following statement.

If you have Server 2003 sp2 (includes the above mentioned fix) then you can right click on your HAL in device manager and downgrade it to single processor WITHOUT any of the workarounds mentioned???

Thanks.