In the BIOS , there is a table that configures/determines a number of hardware values for ACPI and your system to use. One of the features of ACPI is that the values and methods used can be differentiated at boot time depending on what OS you run. Each version of MS Windows has a unique identifier and while Linux can identify as "Linux" , the Linux ACPI gurus have decided that Linux will always identify itself as "Windows NT" . Even if you force Linux to identify itself as Linux, the Linux ACPI code still lies to the BIOS , except for the computers specifically listed in drivers/acpi/blacklist . If you are running very new hardware intended for Windows Vista or Windows 8, you might get better performance on ACPI -related issues if you identify, or "spoof", your Linux OS as Vista or Windows 8 )or a later version of Windows). This is done by adding the boot-time kernel parameter of acpi_osi="Windows 2006" or "Windows 2012" resp
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