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Q83436: Windows 3.1 Resource Kit SYSTEM.INI [386ENH] Section M-Z

Article: Q83436
Product(s): Microsoft Windows 3.x Retail Product
Version(s): 
Operating System(s): 
Keyword(s): 
Last Modified: 15-DEC-2000

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Windows versions 3.1, 3.11 
-------------------------------------------------------------------------------

SUMMARY
=======

This article contains information from the SYSINI.WRI file that ships in the
Microsoft Windows Resource Kit for the Microsoft Windows operating system
version 3.1. You can view SYSINI.WRI within Microsoft Windows Write.

The [386ENH] section of the SYSTEM.INI file contains information specific to
running Windows in 386 enhanced mode, including information used for
virtual-memory page swapping.

MORE INFORMATION
================

===============================================================================

MapPhysAddress=<range>
Default:  None
Purpose:  Specifies the address range (in megabytes) in
         which the memory manager preallocates physical
         page-table entries and linear address space. Use
         this setting if you are using a DOS device driver
         (such as an older version of RAMDrive that uses
         extended memory) that needs contiguous memory.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

MaxBPs=<number>
Default:  200
Purpose:  Specifies the maximum number of break points (a
         method for transferring control to 386 Enhanced
         Windows) that can be used by the Virtual Memory
         Manager. You may need to increase this value if
         you are using a third-party virtual device driver
         that requires more break points than the default
         value.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

MaxCOMPort=<number>
Default:  4
Purpose:  Specifies the maximum number of COM ports
         supported in enhanced mode. Change this value if
         you have more than 4 COM ports installed in your
         computer.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

MaxDMAPGAddress=<address>
Default:  0FFFh (non-EISA computers); 0FFFFFh (EISA
         computers)
Purpose:  Specifies the maximum physical page address that
         can be used for Direct Memory Access (DMA). This
         setting works only with hard drives that support
         DMA.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

MaxPagingFileSize=<kilobytes>
Default:  50 percent of available disk space
Purpose:  Specifies the maximum size (in kilobytes) for a
         temporary swap file.
To change:  Choose the 386 Enhanced icon from the Control
           Panel window.

===============================================================================

MaxPhysPage=<hexidecimal-page-number>
Default:  Determined by Windows based on the highest
         physical page number detected by the Memory
         Manager during initialization.
Purpose:  Specifies the maximum physical page number that
         the Memory Manager can manage as a useable page.
         This setting allows pages to be added at a
         physical address beyond what the Memory Manager
         recognized during initialization. If the value
         specified is less than what the Memory Manager
         determines, the Memory Manager will ignore several
         physical pages that it would normally use,
         preventing the use of memory. This is useful if
         you are using a hardware device that cannot
         recognize all of the physical memory in your
         computer (for example, ISA DMA Network cards
         cannot access physical memory above 16 megabytes.)
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

MCADMA=<Boolean>
Default:  True for MCA computers; False for all other
         computers
Purpose:  Specifies whether Windows should use the MCA
         extensions to direct- memory access (DMA). This
         setting only applies to MCA computers. Disable
         this setting if you are using an MCA computer, but
         the DMA extensions are not implemented.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

MessageBackColor=<vga-color-attribute>
Default:  1 (for blue)
Purpose:  Specifies the background color of message screens,
         such as the screen that appears when you press
         Ctrl+Alt+Del.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

MessageTextColor=<vga-color-attribute>
Default:  F (for white)
Purpose:  Specifies the color used to display text in
         message screens, such as the screen that appears
         when you press Ctrl+Alt+Del.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

MinTimeSlice=<milliseconds>
Default:  20
Purpose:  Specifies the minimum amount of time (in
         milliseconds) a virtual machine is allowed to run
         before other virtual machines can take over. A
         smaller value (such as 10 milliseconds) will make
         multitasking appear smoother, but will decrease
         overall system performance.
To change:  Choose the 386 Enhanced icon from the Control
           Panel window.

===============================================================================

MinUnlockMem=<kilobytes>
Default:  40
Purpose:  Specifies the amount of memory that must remain
         unlocked and available for use when resuming a
         virtual machine if more than one virtual machine
         is running.
To change:  Use Notepad to edit the SYSTEM.INI file. (You
           should never need to change this setting.

===============================================================================

MinUserDiskSpace=<kilobytes>
Default:  500
Purpose:  Specifies how much disk space (in kilobytes) to
         leave free when creating a temporary swap file.
         Use this setting if your system's paging drive has
         less available space than Windows can use for
         paging. This setting does not apply if a permanent
         swap file exists.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

Mouse=<filename-or-*devicename> (See "Device=", above)
Default:  None (Setup assigns an appropriate value based on
         your system configuration.)
Purpose:  Specifies the virtual device that controls the
         mouse hardware in 386 enhanced mode.
To change:  Choose the Windows Setup icon from the Main
           Group window.

===============================================================================

MouseSoftInit=<Boolean>
Default:  True
Purpose:  Specifies whether Windows should convert INT 33h
         function 0 hard initialization calls to function
         33 soft initialization calls, which do not reset
         the mouse hardware. If enabled, you can use a
         mouse with a non-Windows application that you
         start in a window. Disable this setting if the
         cursor and screen information appear garbled or
         distorted when using the mouse with an
         application. If you disable this setting, you may
         not be able to use the mouse when running a non-
         Windows application in a window.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

NetAsynchFallback=<Boolean>
Default:  False
Purpose:  If enabled, Windows attempts to save a failing
         NetBIOS request. When an application issues an
         asynchronous NetBIOS request, Windows will attempt
         to allocate space in its global network buffer to
         receive the data. If there is insufficient space
         in the global buffer, Windows will normally fail
         the NetBIOS request. If this setting is enabled,
         Windows will attempt to save such a request by
         allocating a buffer in local memory and preventing
         any other virtual machines from running until the
         data is received or the timeout period (specified
         by the NetAsynchTimeout setting) expires.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

NetAsynchTimeout=<seconds>
Default:  5.0
Purpose:  Specifies the timeout period (in seconds) when
         Windows needs to enter a critical section in order
         to service an asynchronous NetBIOS request. It is
         used only when NetAsynchFallback is enabled. This
         value can include a decimal (such as 0.5).
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

NetDMASize=<kilobytes>
Default:  32 on Micro Channel (TM) machines (IBM PS/2 or
         compatible); 0 on non-Micro Channel machines (IBM
         PC/AT compatible).
Purpose:  Specifies the DMA buffer size (in kilobytes) for
         NetBIOS transport software if a network has been
         installed. In this case, the buffer size is the
         larger value between this value and the value of
         DMABufferSize.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

NetHeapSize=<kilobytes>
Default:  12
Purpose:  Specifies the size (in kilobytes) of the data-
         transfer buffers in conventional memory that
         Windows allocates for transferring data over a
         network when running in 386 enhanced mode. All
         values are rounded up to the nearest 4K.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

Network=<filename-or-*devicename> (See "Device=", above)
Default:  None (Setup assigns an appropriate value based on
         your system configuration.)
Purpose:  Specifies the type of network you are using with
         Windows in 386 enhanced mode.
To change:  Choose the Windows Setup icon from the Main
           Group window.

===============================================================================

NMIReboot=<Boolean>
Default:  No
Purpose:  If enabled, causes a reboot to occur when a
         nonmaskable interrupt is received.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

NoEMMDriver=<Boolean>
Default:  False
Purpose:  If enabled, prevents Windows in 386 enhanced mode
         from installing its expanded memory driver. This
         differs from setting EMMSize to zero, which does
         not prevent the EMM driver from being loaded.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

NoWaitNetIO=<on-or-off>
Default:  On
Purpose:  Specifies whether or not to convert synchronous
         NetBIOS commands to asynchronous commands. When
         this setting is enabled, synchronous NetBIOS
         commands are converted. This can improve overall
         system performance when running several
         applications.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

OverlappedIO=<Boolean>
Default:  Off, if InDOSPolling is enabled; Otherwise, On
Purpose:  If enabled, several virtual machines can make read
         and write requests to  a disk before the first
         request has been completed. If disabled, virtual
         machines cannot issue a request to read or write
         to a disk until any previous read and write
         requests have been completed.
To change:  Use Notepad to edit the SYSTEM.INI file. (You
           should never need to change this setting.

===============================================================================

PageBuffers=<number>
Default:  4
Purpose:  Specifies the number of 4K page buffers used to
         store asynchronous read and write pages. This
         setting is used only if you are using 32-Bit Disk
         Access and a permanent swap file. You can specify
         a value between 0 and 32. Increasing this value
         can improve Windows' performance.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

PageOverCommit=<number>
Default:  4
Purpose:  Specifies the multiplier for determining the
         amount of linear address space the Memory Manager
         will create for the system. The amount of linear
         address space that the Memory Manager will create
         is computed by rounding up the amount of available
         physical memory to the nearest 4 megabytes and
         then by multiplying that value to the value
         specified for this setting. You can specify a
         value between 1 and 20. Increasing this value
         increases the amount of available linear address
         space, causing the size of data structures to
         increase. This also increases paging activity
         proportionately and can slow down the system.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

Paging=<Boolean>
Default:  Yes
Purpose:  Enables or disables demand paging (virtual memory)
         and permanent and temporary swap files. Disable
         this setting only if you need the disk space
         normally used for a temporary swap file.
To change:  Choose the 386 Enhanced icon from the Control
           Panel window.

===============================================================================

PagingDrive=<drive-letter>
Default:  None
Purpose:  Specifies the disk drive where Windows in 386
         enhanced mode will create a temporary swap file.
         This setting is ignored if you have a permanent
         swap file. If you don't have a permanent swap file
         and no drive is specified or the specified drive
         does not exist, Windows will attempt to put your
         temporary swap file on the drive containing your
         SYSTEM.INI file. If the specified drive is full,
         paging will be disabled.
To change:  Choose the 386 Enhanced icon from the Control
           Panel window.

===============================================================================

PagingFile=<path-and-filename>
Default:  WINDOWS\WIN386.SWP
Purpose:  Specifies the path and filename for the temporary
         swap file that is created when you start Windows
         in 386 enhanced mode. This file is deleted when
         you quit Windows. This setting overrides the
         PagingDrive setting.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

PerformBackfill=<Boolean>
Default:  Auto (Windows automatically checks to see if it
         needs to fill in memory  based on how DOS is
         occupying memory.)
Purpose:  Specifies whether or not to allocate a full 640K
         of memory to a computer that has less than 640K of
         base conventional memory. Enabling or disabling
         this setting overrides the automatic checking done
         by Windows.
To change:  Use Notepad to edit the SYSTEM.INI file. (You
           should never need to change this setting,
           because Windows can automatically detect whether
           or not to perform a backfill.

===============================================================================

PermSwapDOSDrive=<drive-letter>
Default:  None
Purpose:  Specifies the disk drive where Windows in 386
         enhanced mode will create a permanent swap file.
         This setting is ignored if you are using a
         temporary swap file.
To change:  Choose the 386 Enhanced icon from the Control
           Panel window.

===============================================================================

PermSwapSizeK=<kilobytes>
Default:  None
Purpose:  Specifies the desired size in kilobytes of a
         permanent swap file.
To change:  Choose the 386 Enhanced icon from the Control
           Panel window.

===============================================================================

PerVMFILES=<number>
Default:  10; 0 if SHARE is installed.\177
Purpose:  Specifies the number of private file handles
         Windows should allocate to each virtual machine.
         Increase this value if an application does not
         have enough file handles to run. The total number
         of file handles, including the global handles
         specified in the FILES= statement in CONFIG.SYS,
         cannot exceed 255. If it exceeds 255, this value
         will be rounded down. Set this value to 0 to
         prevent the allocation of any private file
         handles. If SHARE is installed, then this setting
         is ignored in the SYSTEM.INI file.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

PSPIncrement=<number>
Default:  2
Purpose:  Specifies the amount of additional memory, in 16-
         byte increments, that Windows should reserve in
         each successive virtual machine when the
         UniqueDOSPSP setting is enabled. The setting that
         works best for your  machine might vary depending
         on your memory configuration and the applications
         you are running. Valid values are 2 through 64.
         See UniqueDosPSP for more information.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

ReflectDosInt2A=<Boolean>
Default:  False
Purpose:  Indicates whether Windows should consume or
         reflect DOS INT 2A signals. The default means
         Windows will consume these signals and therefore
         run more efficiently. Enable this setting if you
         are running memory-resident software that relies
         on detecting INT2A messages.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

ReservedHighArea=<paragraph-range>
Default:  None
Purpose:  Specifies a range of memory that Windows will not
         scan to find unused address space. This has the
         side effect of turning off the RAM and ROM  search
         code for the range. The range (two paragraph
         values separated by a hyphen) must be between A000
         and EFFF. This scanning can interfere with some
         adapters that use the same memory area. The
         starting value is rounded down and the ending
         value is rounded up to a multiple of 4K. For
         example, you could set ReservedHighArea=E100-E3FF
         to prevent Windows from scanning the first 12K of
         memory starting at E100. You can specify more than
         one range by including more than one
         ReservedHighArea line.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

ReservePageFrame=<Boolean>
Default:  True
Purpose:  Specifies whether Windows should give preference
         to EMS page frame space or conventional memory
         when it has to use one of the two to allocate MS-
         DOS transfer buffers. This choice is necessary
         when Windows cannot find space (other than EMS
         page frame space) between 640K and 1MB. If
         enabled, this setting will preserve EMS page frame
         space at the expense of conventional memory. If
         your non-Windows applications do not require
         expanded memory, disable this setting to make more
         conventional memory available to non-Windows
         applications.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

ReserveVideoROM=<Boolean>
Default:  False
Purpose:  Instructs Windows that video read-only memory
         exists in pages C6 and C7. If the text font
         appears scrambled when starting non-Windows
         applications, enable this setting.
To change:  Use Notepad to edit the SYSTEM.INI file. (You
           should not need to change this setting, because
           the default setting causes Windows to detect
           video ROM correctly.)

===============================================================================

ROMScanThreshold=<number>
Default:  20
Purpose:  Specifies a parameter used for determining if a
         memory area in the adapter region (usually between
         C000-EFFF) that has no ROM header or incorrect
         header information is read-only memory (ROM). The
         number for this setting specifies how many
         different values must occur within the memory area
         to determine whether or not it is ROM. If the
         number of transitions is greater than the value
         for this setting, Windows recognizes the memory
         as ROM. If the number of transitions is less than
         the value, Windows recognizes the memory as usable
         memory. A value of 0 disables this setting,
         causing Windows to recognize this memory area as
         usable.
To change:  Use Notepad to edit the SYSTEM.INI file. (You
           should never need to change this setting.)

===============================================================================

ScrollFrequency=<number>
Default:  2
Purpose:  Specifies the number of lines you can scroll in a
         non-Windows application that is running in a
         Window before its display is updated.
To change:  Use Notepad to edit the SYSTEM.INI file. (You
           should never need to change this setting.)

===============================================================================

SGrabLPT=<port-number>
Default:  None
Purpose:  Routes all printer interrupts on the specified
         port to the Windows screen rather than to the
         current virtual machine.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

SyncTime=<Boolean>
Default:  True
Purpose:  If enabled, Windows periodically synchronizes its
         time with the computer's CMOS clock. If this
         setting is disabled, Windows usually maintains the
         correct time, unless TrapTimerPorts is disabled
         and you are running applications that can cause
         the system time to run faster or slower than the
         actual time. This setting is related to the
         TrapTimerPorts setting.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

SystemROMBreakPoint=<Boolean>
Default:  True if Windows is started in real mode of the
         80386/486 CPU. False if Windows is started in
         virtual mode of the 80386/486 CPU. Most 386 memory
         managers, such as QEMM and 386MAX, require this
         value to be set to false. If a 386 memory manager
         is running Windows is started in virtual mode.
         Otherwise, Windows is started in real mode.
Purpose:  Specifies whether Windows should use ROM address
         space between F000:0000 and 1MB for a break point.
         Windows in 386 enhanced mode normally searches
         this space to find a special instruction that is
         used as a system break point. If this address
         space contains something other than permanently
         available ROM, you should disable this setting.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

SysVMEMSLimit=<number -or-kilobytes>
Default:  2048
Purpose:  Specifies how many kilobytes of expanded memory
         Windows is permitted to use. Setting this value to
         0 prevents Windows from gaining access to any
         expanded memory. Setting it to -1 gives Windows \ 
         all the available expanded memory that it
         requests.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

SysVMEMSLocked=<Boolean>
Default:  No
Purpose:  Specifies whether to swap expanded memory being
         used by Windows applications to the hard disk.
         Locking expanded memory (enabling this setting)
         can improve the performance of a Windows
         application that uses it, but can slow down the
         rest of the system.
To change:  Use Notepad to edit the SYSTEM.INI file. (You
           should never need to change this setting.)

===============================================================================

SysVMEMSRequired=<kilobytes>
Default:  0
Purpose:  Specifies how many kilobytes of expanded memory
         must be free in order to start Windows. Leave this
         setting at zero if no Windows applications require
         expanded memory.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

SysVMV86Locked=<Boolean>
Default:  False
Purpose:  If enabled, causes the virtual-mode memory used in
         the system virtual machine to remain locked in
         memory instead of swaping it out to disk.
To change:  Use Notepad to edit the SYSTEM.INI file.
           (Because Windows controls this process, there is
           no need to change this setting.)

===============================================================================

SysVMXMSLimit=<number-or-kilobytes>
Default:  2048
Purpose:  Specifies the maximum amount of memory (in
         kilobytes) the extended  memory driver allocates
         to DOS device drivers and memory-resident software
         in the system virtual machine. Set the value to -1
         to give an application all the available extended

         memory that it requests.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

SysVMXMSRequired=<kilobytes>
Default:  0
Purpose:  Specifies how many kilobytes of extended memory
         must be reserved by the XMS driver in order to
         start Windows. Leave this setting at zero if there
         are no XMS users in the system virtual machine.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

TimerCriticalSection=<milliseconds>
Default:  0
Purpose:  Instructs Windows to go into a critical section
         around all timer interrupt code, and specifies a
         timeout period (in milliseconds). Specifying a
         positive value causes only one virtual machine at
         a time to receive timer interrupts. Some networks
         and other global memory-resident software may fail
         unless this setting is used. However, it slows
         down performance and can make the system seem to
         stop for short periods of time.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

TokenRingSearch=<Boolean>
Default:  True
Purpose:  If enabled, Windows searches for a token ring
         network adapter on machines with IBM PC/AT (R)
         architecture. Disable this setting if you are not
         using a token ring card and the search interferes
         with another device.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

TranslateScans=<Boolean>
Default:  No
Purpose:  If enabled, Windows will translate a keyboard's
         scan codes to make them compatible with standard
         IBM scan codes. Use this setting only if you  have
         a keyboard that generates non-standard scan codes.
         This setting is used only for the Switcher Screen
         and fullscreen message boxes.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

TrapTimerPorts=<Boolean>
Default:  True
Purpose:  Specifies whether Windows should trap read and
         write operations to the system timer ports that
         are performed by applications. If disabled,
         Windows will not trap these operations, allowing
         applications that fequently read or write to the
         timer to run faster. However, this may interfere
         with Windows' ability to keep accurate system
         time. If disabled, Windows can usually detect when
         an application has changed the timer interrupt
         interval and then make any adjustments to the
         time. If your system's time appears to be running
         fast or slow, enable this setting. If you do not
         want to enable this setting, enable the SyncTime
         setting. This causes Windows to check the time
         periodically and then make any necessary
         adjustments.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

UniqueDOSPSP=<Boolean>
Default:  True (If you are running a network based on
         Microsoft Network or LAN Manager. See the
         NETWORKS.WRI online document to find out whether
         the network you are running is one of these);
         False for all other networks.
Purpose:  If enabled, Windows starts every application at a
         unique address (PSP). Each time Windows creates a
         new virtual machine to start a new application,
         Windows reserves a unique amount of memory (i
         bytes) below the application. For example, if the
         first application is loaded at address M, the
         second application is loaded at address M+i, the
         third at M+2i, and so on.The amount of memory (i)
         is determined by the PSPIncrement setting. These
         settings ensure that applications in different
         virtual machines all start at different addresses.
         Some networks use applications' load addresses to
         identify the different processes using the
         network. Disabling this setting on such networks,
         might cause one application to fail when you exit
         another because the network interprets them as the
         same application. If you enable this setting,
         slightly less memory is available for non-Windows
         applications.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

UseableHighArea=<paragraph-range>
Default:  None
Purpose:  Specifies a range of memory that Windows will
         treat as unused address space regardless of what
         may be there. UseableHighArea takes precedence
         over ReservedHighArea if you specify ranges that
         overlap. The range (two values separated by a
         hyphen) must be between A000 and EFFF. The
         starting value is rounded down and the ending
         value is rounded up to a multiple of 4K. For
         example, you could set UseableHighArea=E100-E3FF
         to ensure that Windows can use the first 12K of
         memory starting at E100. You may specify more
         than one range by including more than one
         UseableHighArea line.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

UseInstFile=<Boolean>
Default:  False
Purpose:  Specifies whether Windows should look in the
         INSTANCE.386 file for information it can use to
         determine whether data structures within MS-DOS
         need to be local. There are two other methods for
         giving Windows this information: internal tables
         within the device, and an INT 2Fh call documented
         in the OEM Adaptation Kit. Both methods are
         preferable to using this setting; it is provided
         only for compatibility with Windows/386 version
         2.x.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

UseROMFont=<Boolean>
Default:  True
Purpose:  If enabled, Windows uses the soft font stored in
         the video read-only memory (ROM) for displaying
         messages that appear when non-Windows applications
         are running in a full screen, and for displaying
         the text that appears when switching away from a
         non-Windows application. Disable this setting if
         the font used to display messages is different
         than the font used in the application, or if
         random dots and shapes appear on your screen.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

VGAMonoText=<Boolean>
Default:  True
Purpose:  Instructs Windows to ignore the video memory
         address space in VGA displays, usually used for
         monochrome adapters. When this setting is
         disabled, Windows can use the B000h through B7FF
         range for upper memory space, provided that no
         hardware device is using these addresses and your
         applications do not use the monochrome display
         mode of your VGA adapter.

Note:  This setting applies to VGA displays only.

To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

VideoBackgroundMsg=<Boolean>
Default:  True
Purpose:  If enabled, Windows displays a message when a
         background application is suspended, or if its
         display cannot be updated properly because video
         memory is low. Disabling this setting turns off
         the warning message. This setting affects all non-
         Windows applications that are currently running.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

VideoSuspendDisable=<Boolean>
Default:  False
Purpose:  Specifies whether or not to suspend applications
         running in the background if their display become
         corrupted. If this setting is enabled, the
         application continues running. If disabled,
         applications become suspended and a warning
         message appears, if the VideoBackgroundMsg setting
         is enabled.

Note:  This setting applies to VGA displays only.

To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

VirtualHDIrq=<Boolean>
Default:  On for AT-compatible computers; Off for all other
         computers.
Purpose:  If enabled, Windows in 386 enhanced mode can
         terminate interrupts from the hard disk
         controller, bypassing the ROM routine that handles
         these interrupts. Some hard drives might require
         this setting to be disabled in order for
         interrupts to be processed correctly. If this
         setting is disabled, the ROM routine handles the
         interrupts, which slows down system performance.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

WindowKBRequired=<kilobytes>
Default:  256
Purpose:  Specifies how much conventional memory (in
         kilobytes) must be free in order to start Windows.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

WindowMemSize=<number-or-kilobytes>
Default:  -1
Purpose:  Limits the amount of conventional memory Windows
         can use for itself. The default value (-1)
         indicates that Windows can use as much
         conventional memory as it needs. If there is not
         enough memory to run Windows in 386 enhanced mode,
         try entering a positive value less than 640.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

WindowUpdateTime=<milliseconds>
Default:  50
Purpose:  Specifies the amount of time (in milliseconds)
         Windows takes before it updates the display oXf
         non-Windows applications running in a window.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

WinExclusive=<Boolean>
Default:  No
Purpose:  If enabled, all of the computer's processing time
         is allocated to Windows whenever a Windows
         application is in the foreground. If this setting
         is enabled and a Windows application is in the
         foreground, no non-Windows application will run.
To change:  Choose the 386 Enhanced icon from the Control
           Panel window.

===============================================================================

WinTimeSlice=<number,number>
Default:  100,50
Purpose:  This setting contains two numbers. The first
         number specifies the relative amount of processing
         time (based on the MinTimeSlice setting) given to
         all Windows applications running in the
         foreground, relative to the time allocated to all
         non-Windows applications running in the
         background. The second number specifies the
         relative amount of processing time given to all
         Windows applications running in the background
         when a non-Windows application is running in the
         foreground. The range of valid numbers is 1
         through 10000. The important value is the ratio of
         these settings to the corresponding settings in
         the PIF's of the active non-Windows applications.
To change:  Choose the 386 Enhanced icon from the Control
           Panel window.

===============================================================================

WOAFont=<font filename>
Default:  DOSAPP.FON
Purpose:  Specifies which font file(s) are loaded into
         memory when running non-Windows applications.
         These fonts are also available to your Windows
         applications as long as a non-Windows application
         is running.
To change:  Quit Windows and then run Setup from MS-DOS.
           This setting changes when you change the
           Codepage or Display setting in Setup.
___________________________________________________________
XlatBufferSize=<kilobytes>
Default:  8
Purpose:  Specifies the size of the low-memory buffer used
         to map MS-DOS calls from protected mode to virtual
         386 enhanced mode. Increasing this value can
         improve the performance of protected mode Windows
         applications that read or write information in a
         large number of bytes (for example, some database
         applications). However, this may decrease the
         amount of memory available for running non-Windows
         applications and may cause problems on networks
         that use named pipes. These networks may require a
         value of 4. The value you specify is rounded to
         the next 4-kilobyte increment. For example, if you
         set this value to 5, Windows rounds it up to 8.
To change:  Use Notepad to edit the SYSTEM.INI file.

===============================================================================

XMSUMBInitCalls=<Boolean>
Default:  Ususally true, but may be false depending on the
         extended memory manager you are using.
Purpose:  Specifies whether or not Windows should call the
         extended memory driver's upper memory block (UMB)
         management routines.
To change:  Use Notepad to edit the SYSTEM.INI file. (You
           should never need to change this setting.)

===============================================================================
Reference(s):

"Microsoft Windows Resource Kit," version 3.1, SYSTEM.INI

Additional query words: 3.10 win31

======================================================================
Keywords          :  
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin310 kbWin311

=============================================================================

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