JSI Tip 0515 - What switches are available in boot.ini?

In tip 055, we introducted c:\boot.ini. The following switches are supported:

/3GB - Moves the starting point of kernel memory to 3 GB, allowing user-mode applications to access 3 GB of memory instead of the default 2 GB.

/BASEVIDEO - forces the system into standard 640x480 16-color VGA mode. This is the default on the second boot menu entry and is used if you installed a video driver that won't boot or display properly.

/BAUDRATE=nnnn - sets baudrate of the debug port. If you do not set the baud rate, the default baud rate is 19,200. 9,600 is the normal rate for remote debugging over a modem. This will also enable the /DEBUG switch. See Q148954.

/CRASHDEBUG - enables the COM port for debugging if Windows NT crashes, but allows you to use the COM port for normal operations. See Q151981.

/DEBUG - enables the kernel debugger. This allows live remote debugging of a Windows NT system through the COM ports. Unlike /CRASHDEBUG, /DEBUG will use the COM port whether or not you are debugging. See Q121543.

/DEBUGPORT=comx - selects a COM port for the debug port. The default is COM2 if it exists, otherwise the default is COM1.

/HAL=filename defines the actual hardware abstraction layer (HAL) to be loaded at startup. This switch is useful in trying out a different HAL before renaming it to hal.dll. This switch is also useful when you want to try booting between multiprocessor and single processor mode when used in conjunction with the /KERNEL switch. See tip 466.

/KERNEL=filename - allows you to define the actual KERNEL to be loaded at startup.

MAXMEM= - The number of megabytes of RAM that NT should see. Must be less than or equal to the actual RAM.

/NODEBUG - disables the kernel debugger, causing a blue screen if a piece of code has a debug hardcoded breakpoint in its software.

/NOSERIALMICE:COMx - disables the mouse port check for this com port. Ports may be separated with commas to disable more than one port. If no serial port is specified then ALL ports will be disabled for mouse devices. If you have a UPS on COM1, you would use /NOSERIALMICE:COM1. See tip 317.

/NUMPROC=n - sets the number of processors that Windows NT will use. This is usefull in load simulation. If you use this switch, it should never to set to more processors than are actually installed. See tip 066.

/PCILOCK - prevents Windows NT from enumerating the PCI bus every time it starts.

/SOS - causes the loader to print the name of loaded modules instead of displaying the dots.

/ONECPU - is part of Compaq's HAL and tells Windows NT to use only 1 CPU.

/WIN95 - loads bootsect.dos - See Q157992.

/WIN95DOS - loads bootsect.w40 - See Q157992.

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