DOCUMENT:Q58383 23-JAN-2002 [win3x] TITLE :Windows 3.0 SYSTEM.INI [386Enh] Section PRODUCT :Microsoft Windows 3.x Retail Product PROD/VER::3.0,3.0a OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows versions 3.0, 3.0a ------------------------------------------------------------------------------- SUMMARY ======= The following information is contained in the Microsoft Windows version 3.0 SYSINI.TXT readme file. The Windows Setup program copies this file to the Windows 3.0 directory. MORE INFORMATION ================ [386Enh] SECTION ---------------- The [386Enh] section contains information specific to running Windows in 386 enhanced mode, including information used for virtual-memory page swapping. The [386Enh] section can contain the following settings: ---------------------------------------------------------------------- AllVMsExclusive= Default: false Purpose: If enabled, this setting forces all applications to run in exclusive mode, overriding all contrary settings in the applications' program information files (PIFs). Enabling this setting might prolong the life of network and memory-resident software that is incompatible with Windows. Can change by: Using Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- AltPasteDelay= Default: .025 Purpose: Specifies how much time Windows waits before pasting any characters after the ALT key has been pasted. Some applications may require more time for recognition of the ALT keystroke. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- CGANoSnow= Default: no Purpose: If enabled, causes Windows to do special handling to avoid snow appearing on an IBM CGA display device. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- COM1AutoAssign= COM2AutoAssign= COM3AutoAssign= COM4AutoAssign= Default: 2 Purpose: Indicate the contention detection values for each connected communications port. These values are used by Windows to determine how to arbitrate requests for the use of a device by more than one application, at least one of which is a non-Windows application. If the value is -1, Windows will display a warning message that asks the user which application should be given control of the port. If the value is zero, any application can use the device at any time. If the value is a positive integer less than 1,000, this value represents the number of seconds after an application stops using the device before another application can use the same device. To change: Choose the 386 Enhanced icon from the Control Panel window. ---------------------------------------------------------------------- COM1Base= COM2Base= COM3Base= COM4Base= Default: See purpose. Purpose: Specifies the base (first) port for the serial port adapter you are using. The default values are as follows: Port Default ---- ------- COM1 3F8h COM2 2F8h COM3 3E8h COM4 2E8h Check your hardware documentation for the appropriate value. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- COMBoostTime= Default: 2 Purpose: Specifies the amount of time (in milliseconds) to allow a virtual machine to process a COM interrupt. If an communications application is losing keyboard characters on the display, you can try increasing this value. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- COM1Irq= COM2Irq= COM3Irq= COM4Irq= Default: See purpose. Purpose: Specifies which interrupt line is being used by the device on the specified communications port. The default values are as follows: Port Default ---- ------- COM1 4 COM2 3 COM3 4 COM4 3 Check your hardware documentation for the appropriate value. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- Device= Default: none Purpose: Specifies which virtual devices are being used with Windows in 386 enhanced mode. This value can appear two ways: either the filename of a specific device driver, or an asterisk (*) followed immediately by the device name. The latter case refers to a virtual device that is in the WIN386.EXE file. Synonyms for device= are display=, keyboard=, network= and mouse=. Multiple device settings are required to run Windows in 386 enhanced mode. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- Display= Default: none Purpose: Specifies the display device that is being used with Windows in 386 enhanced mode. This setting is a synonym to device= and exists to tell Setup which display device driver you are using. To change: Choose the Windows Setup icon from the Main Group window. ---------------------------------------------------------------------- DMABufferIn1MB= Default: no Purpose: Indicates, if enabled, that the DMA buffer memory should be in the first 1 MB of memory in order to be compatible with 8-bit bus master cards. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- DMABufferSize= Default: 16 Purpose: Specifies the amount of memory to be reserved for buffered direct memory access (DMA). Windows in 386 enhanced mode will default to a DMA buffer size that will handle disk access. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- DualDisplay= Default: See purpose. Purpose: Normally, when running in 386 enhanced mode, the memory between B000:0000 and B7FF:FFFF will be used by the general system unless a secondary display is detected. If this setting is enabled, this memory will be left unused and available for display adapters. If this setting is disabled, the address range will available on EGA systems but not under VGA systems, since the VGA display device supports monochrome modes, which use this address space. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- EMMExclude= Default: none Purpose: Specifies a range of memory that Windows will not consider using as an EMM page. 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 C000 and EFFF. Windows normally scans this area to find unused address space. This scanning can interfere with some adapters that use the same memory area. Values are rounded to a multiple of 16K. For example, you could set EMMExclude=C800-CFFF to prevent Windows from scanning the addresses C800:0000 through CFFF:FFFF. You may specify multiple memory ranges by using this setting more than once. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- EMMInclude= Default: none Purpose: Specifies a range of memory that Windows will consider using as an EMM page regardless of what may be there. EMMInclude takes precedence over EMMExclude if you specify ranges that overlap. The range (two values separated by a hyphen) must be between C000 and EFFF. Values are rounded to the nearest 16K. You may specify multiple memory ranges by using this setting more than once. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- EMMPageFrame=
Default: none Purpose: Specifies the starting address where the 64K page frame will begin only when Windows in 386 enhanced mode cannot find a suitable page frame. Allows an EMM page frame in an area containing some unused RAM or ROM. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- EMMSize= Default: -1 Purpose: Specifies the total amount of memory to be made available for mapping as expanded memory. The default allows all system memory to be allocated as EMM. You should specify a value for this setting if you run an application that allocates all of the available expanded memory. This will be apparent if, when you run the application, you can never create any new virtual machine. If this value is zero, then no expanded memory will be allocated, but the EMM driver will be loaded. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- FileSysChange= Default: yes Purpose: Indicates whether File Manager will automatically receive messages anytime a non-Windows application creates, renames, or deletes a file. By disabling this setting , a virtual machine can be run exclusively even when it manipulates files. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- global= Default: (all devices) Purpose: Used to define DOS devices loaded in CONFIG.SYS that need to be global to the system. The default setting for all devices is global. But certain virtual devices might specify that a DOS device be local (for example, MS$MOUSE). Use this setting to override that local specification. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- HighFloppyReads= Default: yes Purpose: Normally, Windows turns a DMA verify to the area E000:0000-EFFF:FFFF into a read. In rare cases, this might cause the system to fail because some software might, as a result, write over the system's shadow RAM if you have it in this area. If this happens, disable this setting and set EMMExclude to E000-EFFF. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- IgnoreInstalledEMM= Default: no Purpose: Enabling this setting allows Windows to start in 386 enhanced mode even when there is an unknown expanded memory manager (EMM) running. This can cause the system to fail if memory-resident software was using EMM before Windows started. Enable this setting only if no such software is installed or you are sure it will not be active when you are running Windows. Note: This only applies to expanded memory managers servicing physical EMS hardware; Windows will not disable 80386 expanded memory emulators. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- InDOSPolling= Default: no Purpose: Some memory-resident software needs to be in a critical section to do operations off an INT21 hook. Enabling this setting assures that this will happen by preventing Windows from running other virtual machines when the memory-resident software has the InDOS flag set. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- IRQ9Global= Default: no Purpose: If enabled, this setting converts IRQ9 masks to global. Enable if you are using software that leaves IRQ9 masks, therefore hanging the system. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- Keyboard= Default: none Purpose: Tells Setup which keyboard driver is being used with Windows in 386 enhanced mode. This is a synonym to device=. To change: Choose the Windows Setup icon from the Main Group window. ---------------------------------------------------------------------- KeyBoostTime= Default: .001 Purpose: Specifies the amount of time an application gets to run with increased priority when it receives a keystroke. This setting can used to increase the response to keystrokes when several background applications are running. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- KeyBufferDelay= Default: .2 Purpose: Specifies the amount of time to delay processing keyboard input after the keyboard buffer is full. Some applications may require a larger value than the default. To change: Use Notepad to edit the SYSTEM.INI file. --------------------------------------------------------------------- KeyPasteDelay= Default: .003 Purpose: Specifies how much time to wait before pasting any characters after a key has been pasted. Some applications may require more time than the default for recognition of a keystroke. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- KeyPasteTimeout= Default: 1 Purpose: Specifies how much time to allow an application to make the necessary BIOS calls after it reads keyboard input before Windows will setting from fast paste to slow paste keyboard input. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- Local= Default: CON Purpose: Used to define device drivers that need to be local to each virtual machine. This means a separate copy of the driver will exist in each virtual machine, and each will keep different state information. Most device drivers will not function properly when this setting is used. An exception is CON, the DOS console device, which should be local to avoid filling a buffer with input from multiple virtual machines. To change: Use Notepad to edit SYSTEM.INI file. ---------------------------------------------------------------------- LPT1AutoAssign= LPT2AutoAssign= LPT3AutoAssign= LPT4AutoAssign= Default: 60 Purpose: Indicates the contention detection value for each connected port. These values are used by Windows to determine how to arbitrate requests for the use of a device by more than one application, at least one of which is a non-Windows application. If the value is -1, Windows will display a warning message that asks the user which application should be given control of the port. If the value is 0, any application can use the device at any time. If the value is a positive integer less than 1,000, this value represents the number of seconds after an application stops using the device before another application can use the same device. To change: Choose the 386 Enhanced icon from the Control Panel window. ---------------------------------------------------------------------- MapLargeNetTransfers= Default: false Purpose: Indicates whether to map a NetBIOS request when there is not enough buffer space to buffer it. Setting this setting to true may be useful if you do not want to use a lot of memory for buffers when running a network application that does large data transfers. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- MapPhysAddress= Default: none Purpose: Specifies the address range (in MB) in which the memory manager will preallocate physical mappings. Use this setting if you are using a DOS device driver (such as an older version of RAMDrive that uses extended memory) that uses the INT15 MOVEBLOCK service to access memory allocated before Windows in 386 enhanced mode is started. Otherwise, if no memory is available, the MOVEBLOCK call may not be made. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- MaxPagingFileSize= Default: none Purpose: Specifies the maximum size for a temporary swap file. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- MinTimeSlice= Default: 20 Purpose: Specifies the minimum amount of time a virtual machine will be allowed to run before other virtual machines may take over. A smaller value (such as 1 millisecond) will make multitasking appear smoother, but will diminish the overall system performance. To change: Choose the 386 Enhanced icon from the Control Panel window. ---------------------------------------------------------------------- MinUserDiskSpace= Default: 500 Purpose: Tells Windows how much disk space to leave free when creating a temporary swap file. You would want to use this setting if your system's paging drive has less available space than Windows can use for paging. This setting has no effect if a permanent swap file exists. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- Mouse= Default: none Purpose: Specifies the virtual device that handles the mouse hardware in 386 enhanced mode. This setting is a synonym for device=. To change: Choose the Windows Setup icon from the Main Group window. ---------------------------------------------------------------------- NetAsynchFallback= Default: false Purpose: 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 VMs from running until the data is received and the timeout period (defined by NetAsynchTimeout) expires. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- NetAsynchTimeout= 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). ---------------------------------------------------------------------- NetDMASize= Default: 32 on Micro Channel machines 0 on non-Micro Channel machines Purpose: Specifies the DMA buffer size 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= Default: 12 Purpose: Specifies the size of the buffers that Windows in 386 enhanced mode allocates in conventional memory for transferring data over a network. All values are rounded up to the nearest 4K. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- Network= Default: none Purpose: Tells Setup which type of network you are using. This setting is a synonym for device=. To change: Choose the Windows Setup icon from the Main Group window. ---------------------------------------------------------------------- NMIReboot= Default: no Purpose: If enabled, causes a reboot to occur when an NMI interrupt is received. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- NoEMMDriver= Default: false Purpose: Causes Windows in 386 enhanced mode to not install 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. ---------------------------------------------------------------------- Paging= Default: yes Purpose: Enables or disables demand paging (virtual memory). You would disable this setting only if you need the disk space normally used for a temporary swap file. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- PagingDrive= Default: (current drive) Purpose: Specifies the disk drive where Windows in 386 enhanced mode will allocate a temporary swap file. If the current drive is a network drive, the swap file will be created on the same drive as the SYSTEM.INI file. If both are network drives, paging will be disabled. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- ReflectDosInt2A= 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. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- ReservePageFrame= Default: true Purpose: Tells Windows whether to use up EMS page frame space when it allocates DOS transfer buffers below 640K. Leaving this setting disabled gives a non-Windows application more memory at the expense of EMS page frame space. Enable this setting only for an application that uses an EMS page frame. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- SGrabLPT= Default: (current virtual machine) Purpose: Routes all printer input on the specified port to the system virtual machine rather than the current virtual machine. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- SystemRomBreakPoint= Default: true Purpose: Windows in 386 enhanced mode normally searches the ROM address space between F000 and 1 MB 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 so that Windows will not use this space for a break point. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- SystemVMPriority= 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 numbers that can be entered is 1 through 10000. The important value is the ratio of these settings to the corresponding settings in the program information files (PIFs) of the active non-Windows applications. To change: Choose the 386 Enhanced icon from the Control Panel window. ---------------------------------------------------------------------- SysVMemsLimit= Default: 0 Purpose: Specifies how many kilobytes of expanded memory Windows should be permitted to use. Leave this setting at zero to prevent Windows from gaining access to any expanded memory. Set it to -1 to give Windows all the available expanded memory that it requests. To change: Choose the PIF Editor icon from the Accessories Group window. ---------------------------------------------------------------------- SysVMemsLocked= Default: no Purpose: Indicates whether to swap Windows' expanded memory to the hard disk. Locking EMS memory can improve Windows performance, but it slows down the rest of the system. To change: Choose the PIF Editor icon from the Accessories Group window. ---------------------------------------------------------------------- SysVMemsRequired= 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 application uses expanded memory. To change: Choose the PIF Editor icon from the Accessories Group window. ---------------------------------------------------------------------- SysVMExclusive= Default: no Purpose: Indicates whether Windows always gets all of the computer's processing time whenever a Windows application is active. If this setting is enabled and a Windows application is in the foreground, no non-Windows applications will run. To change: Choose the 386 Enhanced icon from the Control Panel window. ---------------------------------------------------------------------- SysVMKBDesired= Default: -1 Purpose: Limits the amount of conventional memory Windows can use for itself. The default value indicates that Windows can use as much of this space as it needs. You can try entering a positive value if there is not enough memory to run Windows in 386 enhanced mode. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- SysVMKBRequired= Default: 256 Purpose: Specifies how much conventional memory (in KB) must be free in order to start Windows. Setting this setting to -1 gives Windows all available conventional memory. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- SysVMV86Locked= Default: false Purpose: Enabling this setting will cause the virtual-mode memory being used in the system VM to remain locked in memory rather that being swappable out to disk. Because Windows handles this process, there is no known reason to enable this setting. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- SysVMxmsLimit= Default: 0 Purpose: Specifies the maximum amount of memory the XMS driver will allocate to DOS device drivers and memory-resident software in the system virtual machine. Set to -1 to give an application all the available extended memory that it requests. To change: Choose the PIF Editor icon from the Accessories Group window. ---------------------------------------------------------------------- SysVMxmsLocked= Default: no Purpose: Indicates whether to swap the memory allocated by the XMS driver to the hard disk. Locking the XMS memory can improve an application's performance, but it slows down the rest of the system. To change: Choose the PIF Editor icon from the Accessories Group window. ---------------------------------------------------------------------- SysVMxmsRequired= 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: Choose the PIF Editor icon from the Accessories Group window. ---------------------------------------------------------------------- TokenRingSearch= Default: true Purpose: Tells Windows whether to search for a token ring network adapter on AT architecture machines. Disable this setting if you are not using a token ring card and the search disables another device. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- TranslateScans= Default: no Purpose: Indicates whether Windows will translate a keyboard's scan codes to make them compatible with standard IBM scan codes. This setting is necessary only for keyboards that generate non-standard scan codes. This setting is used only for the Switcher Screen and message boxes. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- TrapFloppyFIFO= Default: on for Micro Channel machines off for other machines Purpose: Indicates whether to enable port trapping in the VFD. When trapping is enabled, the FIFO is never enabled. FIFO can interfere with DMA. Normally, you should disable this setting if there is a port conflict (port is 03F3h). To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- UniqueDOSPSP= Default: false Purpose: If enabled, this setting tells Windows in 386 enhanced mode to reserve some paragraphs of memory in each virtual machine (VM) prior to starting an application in the VM. This will usually ensure that each application has a unique PSP (loading address). Some networks use the PSP to identify a process to make sure that two processes do not try to modify a file at the same time. On such networks, running with this setting disabled may result in corrupted files. However, enabling this setting will take memory away from each application. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- UseInstFile= Default: none Purpose: Specifies a data file that the DOS Manager device (DOSMGR) should use to determine whether data structures within DOS need to be local. There are two other methods to do this: internal tables within the device, and an INT 2fh call documented in the OEM Adaptation Kit. Both methods are preferred 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. ---------------------------------------------------------------------- VirtualHDIrq= Default: on Purpose: Allows Windows in 386 enhanced mode to terminate interrupts from hard disk controller, bypassing the ROM routine that handles these interrupts. Some hard drives might require that this setting be disabled in order for interrupts to be processed correctly. If this setting is disabled, the ROM routine handles the interrupts, which slows the system's performance. To change: Use Notepad to edit the SYSTEM.INI file. ---------------------------------------------------------------------- WindowUpdateTime= Default: 50 Purpose: Specifies the amount of time Windows takes between updates of the display for a windowed non-Windows application. To change: Use Notepad to edit the SYSTEM.INI file. KBCategory: kbref kbdisplay KBSubcategory: win30 Additional query words: Win30 3.00 3.00a \* NOUPD ====================================================================== Keywords : Technology : kbWin3xSearch kbZNotKeyword3 kbWin300 kbWin300a Version : :3.0,3.0a Issue type : kbinfo ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. 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