PC Hardware

Dual-Booting with Windows NT

Windows 95 and Windows NT share the same machine quite well and dual-booting is no problem. However, you must consider the following:

  • The hard disk drive must have a Windows 95 FAT16 partition. NT will run in Windows FAT16, but Windows 95 will not run on NTFS (NT file system).
  • Drive compression for Windows 95 and Windows NT differs and is incompatible. Therefore, you cannot install Windows NT on a Windows partition that uses drive compression.

To avoid reinstalling all the Windows 95 applications in Windows NT, do the following:

  • In the Windows NT Control Panel, open the system icons.
  • In the System dialog box, highlight the Path line in the System Environment Variables section. Move down to the Value text box and add the following string to the end of the existing value:

The Boot Process from Power Up to Startup

There are twelve steps to a successful startup of Windows 95.

  1. Powering on: The system microprocessor executes the ROM BIOS code and initiates the POST (power on self-test). A single beep means success.
  2. Finding a boot sector: The BIOS checks the A drive for a boot sector; if there is no disk in the floppy disk drive, it checks the C drive.
  3. Running the boot program: BIOS runs IO.SYS (or IO.SYS and MSDOS.SYS), initializes some device drivers, and performs a few real-mode chores.
  4. Reading MSDOS.SYS: Remember, this is not the same as with MS-DOS (it is a text file with setup information). After collecting the information from MSDOS.SYS, you will see the "Starting Windows 95" message.
  5. Reading CONFIG.SYS: Commands are processed in CONFIG.SYS file and load real-mode devices.
  6. Reading AUTOEXEC.BAT: Commands are processed in AUTOEXEC.BAT.
  7. Reading the Registry: The Registry data is read and drivers and settings are loaded. The following table describes some of the drivers that can be specified by the Registry along with their functions. They could also be loaded using the CONFIG.SYS file.
  8. Setting Function
    BUFFERS=30 Determines the number of file buffers to create-for backward compatibility.
    DOS=HIGH Loads MS-DOS into high memory.
    DRVSPACE.BIN or DBLSPACE.BIN Disk compression.
    FCBS=4 Determines the number of file control blocks that can be open at one time-for backward compatibility.
    FILES=30 Determines the number of file handles to create- for backward compatibility.
    HIMEM.SYS Loads real-mode extended memory manager.
    IFSHLP.SYS Installable file system helper-helps load VFAT and other Windows 95 installable file systems.
    LASTDRIVE=Z Determines the last drive letter that can be assigned to a disk drive-for backward compatibility.
    SETVER.EXE The operating system version. If an MS-DOS program needs a special version of MS-DOS, this setting can "lie" to MS-DOS so the program will run.
    SHELL=COMMAND.COM /P Determines the name of the command-line interpreter.
    STACKS=9,256 Determines the number of stack frames and the size of each frame-for backward compatibility.
CAUTION
Don't use values less than these defaults.
  1. Switching to Protected Mode: The processor switches to protected mode and loads protected-mode drivers (VMM32.VXD).
  2. Configuring Plug and Play: Windows now loads new device drivers detected during the initial boot phase, resolves hardware conflicts, and performs other tasks.
  3. Loading Windows 95 GUI: The interface is loaded.
  4. Configuring Network: Prompts for network password if applicable (or user password if user profiles are enabled).
  5. Processing Startup Folder: Checks the startup folder and loads any programs found.