A. In a previous FAQ, I described how to change hal.dll.softex to let the machine power down on shutdown. The method I described uses the hal.dll.softex file that comes with NT 4.0 Service Pack 4 (SP4) and later. To power down NT 4.0 without modifying hal.dll, perform the following steps:

  1. Run the service pack installer with the /X parameter to extract files only. The service pack will prompt you to provide the location for the extracted files; provide a location and continue.
  2. After you extract the service pack files, copy ppntapm.sys from the extracted files directory to your drivers directory (usually \%systemroot%\winnt\system32\drivers).
  3. Copy the following lines between the "-- begin" and "-- end" lines to Notepad, and save the file as ppntapm.reg.
                                  -- begin PPNTAPM.REG                              REGEDIT4                              \[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ppntapm\]                              "Group"="Power Management"                              "Start"=dword:00000000                              "Error Control"=dword:00000001                              "Tag"=dword:000000a1                              "Type"=dword:00000001                              \[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ppntapm\Parameters\]                              "UseDefaultSegmentLimits"=dword:00000001                              \[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\]                              "PowerdownAfterShutdown"="1"                              -- end PPNTAPM.REG                               
  4. Double-click the ppntapm.reg file to import the appropriate registry settings.
  5. Reboot your system for the change to take effect.