Dual Core Xeon 3.0GHZ CPU only seen as one CPU in Windows Server 2003

I have a Dual Core Xeon 3.0Ghz CPU in a Wndows Server 2003 box. Device manager lists 2 processors in the "Processors" section. However when you go to task manager, it only shows 1 CPU. On an identical setup, but newer installation of Windows Server 2003 on another box, it sees both processors, no problem. How would I get Windows to use both processors?
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On the Server that is operating properly open the device manager and expand the "Computer" menu. Take note of the ACPI listing. Compare it to the server that is not functioning correctly. I'm guessing they will be different.
Update that driver by
A - Using the update feature as you would with any other driver, if you know the location of the correct ACPI driver, the Mobo cd should have it.
B - Uninstalling it and hoping the PnP gets it right the second time

Other than ACPI this may still be a bios issue. Double check as always.

Good Luck, and let me know!

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Do you have SP1 installed also ?
NeoGeminiAuthor Commented:
Yes, SP1 is installed.
May be a silly question, but do you have Task manager set to one graph for all CPUs or one graph per CPU?

Go to Task Manager->Performance select the View Menu->CPU History and see what it says there.

Dave Dietz
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Windows Server 2003

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