Unknown Device in Device Manager - Microsoft ACPI-Compliant System

Hello all,

I have just built a new computer using an ASUS P5N-E SLI motherboard, Intel Q6600 CPU, 4GB G.skill RAM, (2) ASUS 7300GT video cards, 3 hard disk drives on a COMBOX driver swapper controller (This allows me to choose which drive to boot from). On drive (1) I have installed Windows 2003 Server and have it configured as a workstation (Perfect install and all devices recognized).  On drive (2) I have installed Windows XP Professional x64 (Problems here).  On Drive (3) I have installed Windows Vista x64 (Perfect install and all devices recognized).

My problem is with the intstallation on drive (2 - Windows XP Pro x64), everything installed and working with no problems, with the exception of 4 Unknown device lines in Device Manager.  When viewing devices by connection these 4 lines are listed under Microsoft ACPI-Compliant System.  

In the properties for these drivers the details tab Device Instance Id shows the values "ACPI\GENUINEINTEL_-_EM64T_FAMILY_6_MODEL_15\_0", "ACPI\GENUINEINTEL_-_EM64T_FAMILY_6_MODEL_15\_1", "ACPI\GENUINEINTEL_-_EM64T_FAMILY_6_MODEL_15\_2" and "ACPI\GENUINEINTEL_-_EM64T_FAMILY_6_MODEL_15\_4" for each unknown device.  The Compatible Ids show value: ACPI\Processor.

When I boot into my Windows 2003 OS the driver details for the devices point to "C:\Windows\System32\drivers\intelppm.sys" as the proper driver.  When in my Windows XP x64 OS I have the Unknown device question marks. There is also no registry entry for [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\intelppm].  The Windows 2003 install on drive 1 has a registry entry for this key.

All drivers have been downloaded and installed from the ASUS website and as stated above, everything seems to be working properly.  I just want to clear up the Unknown device question marks.  I think that the Q6600 processor driver is not being detected properly during the initial setup or after I load xp x64 SP2.

I have re-loaded the Windows XP Pro x64 OS three times.  I have been on the phone with Microsoft, ASUS and Intel with no help from either of these sources and have searched the internet for 2 days for solutions and/or a driver to solve this problem.  I have not installed any other software other than the OS.

Two questions:
(1) Does Windows XP Pro x64 support quad core processors?
(2) What harm will it be or what problems may occur going forward  if I just disable these devices and move on?.

I have tried all that I know and have searched forums, newsgroups, etc. with no success.  Please help.  I wanted to install/test both OSes as Windows XP Professional 32-bit does not recognize my 4GB of RAM.

Thanks much in advance.Start Free Trial