Your event log contains postings that are similar to:

Source: ACPI                              Category: None                              Type: Error                              Event ID: 12                              User: N/A                              Computer: Machine_Name                              Description: AMLI: ACPI BIOS is attempting to create an illegal memory OpRegion,                                           starting at address 0x400, with a length of 0x100. This region lies                                           in the Operating system's protected memory address range (0x0 - 0x9fc00).                                           This could lead to system instability. Please contact your system vendor                                           for technical assistance. For more information, For more information,                                           see Help and Support Center at: http://go.microsoft.com/fwlink/events.asp                              Source: ACPI                              Category: None                              Type: Error                              Event ID: 5                              User: N/A                              Computer: Machine_Name                              Description: AMLI: ACPI BIOS is attempting to write to an illegal IO port address (0xcf8),                                           which lies in the 0xcf8 - 0xcff protected address range. This could lead                                           to system instability. Please contact your system vendor for technical assistance.                                            For more information, see Help and Support Center at:                                            http://go.microsoft.com/fwlink/events.asp                              Source: ACPI                              Category: None                              Type: Error                              Event ID: 4                              User: N/A                              Computer: Machine_Name                              Description: AMLI: ACPI BIOS is attempting to read from an illegal IO port address (0xcfc),                                           which lies in the 0xcf8 - 0xcff protected address range. This could lead to                                           system instability. Please contact your system vendor for technical assistance.                                            For more information, see Help and Support Center at:                                           http://go.microsoft.com/fwlink/events.asp
If you computer's BIOS tries to write to a port in ACPI Machine Language ( AML), you will receive similar errors. Windows NT-based computers, including Windows XP and Windows Server 2003, do NOT allow these operations as they can cause instability.

To resolve this problem, contact your manufacturer about a BIOS upgrade.