I have a HP Proliant DL360 G4 server running Windows 2003 Server. It has one Intel Xeon 3.4 GHz processor. The Intel Processor ID Utility shows that this processor supports Hyper threading. Having a processor that supports hyper threading, I expect to see two processors/cores shown on the performance tab in task manager, but I only see one.
In task manager, I have checked the View->CPU History option and it is set to "One Graph per CPU" (in fact thats the only option given).
I have also tried changing the environmental variable "Number_Of_Processors" from "1" to "2" and reboot but the setting always reverts back to "1" after a reboot and task manager is no different than before.
Device Manager does show "ACPI Multiprocessor PC" under "Computer", which I believe is correct for this type of cpu.