DOCUMENT:Q84015  17-DEC-2000  [msdos]
TITLE   :Adaptec 1740 Controller Requires Double Buffering
PRODUCT :Microsoft Disk Operating System
PROD/VER:MS-DOS:4.x,5.0,6.0; WINDOWS:3.0,3.0a,3.1,3.11
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft MS-DOS operating system versions 4.0, 4.01, 5.0, 6.0 
 - Microsoft Windows versions 3.0, 3.0a, 3.1 
 - Microsoft Windows for Workgroups versions 3.1, 3.11 
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SUMMARY
=======

According to Adaptec documentation, using the Adaptec 1740 controller with
Windows in enhanced mode or with the EMM386.SY/EMM386.EXE device driver requires
a double buffering device driver.

However, if SMARTDrive (SMARTDRV.EXE) version 4.0 from Microsoft Windows version
3.1, is installed to perform double buffering, it may not detect that double
buffering is required. If you are using SMARTDrive version 4.0, you can force
SMARTDrive to perform double buffering by loading it with "/DOUBLE_BUFFER+". For
example:

       device=c:\windows\smartdrv.exe /double_buffer+

If you are not using Windows 3.1, you can force SMARTDRV.SYS from MS-DOS 5.0 or
Windows 3.0 to perform double buffering by loading it with "/b+". For example:

      device=c:\dos\smartdrv.sys /b+

MORE INFORMATION
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When providing double buffering, SMARTDRV.SYS cannot be loaded into upper memory
blocks (UMBs).

SMARTDRV.EXE (which is SMARTDrive version 4.0, included with Windows 3.1)
separates the double buffering and disk caching functions. The double buffering
portion is loaded in CONFIG.SYS and must be loaded in conventional memory. The
disk cache portion of SMARTDrive is loaded from the AUTOEXEC.BAT file, and can
be loaded into upper memory if an upper memory block (UMB) provider such as
EMM386.EXE is loaded.

For more information on double buffering, query on:

   double buffering definition

Additional query words: 3.00 3.00a 3.10 3.11 5.0 5.00 5.0a 4.00 4.01 4.01a 3rdparty

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Keywords          :  
Technology        : kbAudDeveloper kbWin3xSearch kbWFWSearch kbZNotKeyword3 kbWin300 kbWin300a kbWin310 kbWFW310 kbWFW311 kbMSDOSSearch kbMSDOS400 kbMSDOS600 kbMSDOS500 kbMSDOS401
Version           : MS-DOS:4.x,5.0,6.0; WINDOWS:3.0,3.0a,3.1,3.11

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