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I'm investigating a bug which only seems to be reproducable on some single processor machines. I want to know if this is related to the HAL.

Prior to Server 2008, it was possible to select a specific HAL .dll using device manager as described here - Halapic.dll is uniprocessor and Halmps.dll multi.

In Server 2008, I can see three .dlls listed under drivers for my computer. The naming convention suggests that 2008 always has drivers for standard PC, uniproc pc and multiproc pc.

My question is this: Does Server 2008 always use a uniproc HAL on a machine with a single CPU? Additionally, is there a way to determine which HAL you use, or to force use of a particular HAL?


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I believe only the ACPI HAL ships with Windows Server 2008. Mark Russinovich mentioned something about it when discussing the changes to the kernel. Geoff Chappell has some great history on the HALs.

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My understanding is that the Vista/Server 2008 kernel is HAL agnostic and you won't see dll differences in the dll's between a multi-proc and single-proc system.

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