DOCUMENT:Q134295  04-FEB-2002  [win95x]
TITLE   :Computer May Hang with Cyrix Processor and ACC2066 Chip Set
PRODUCT :Microsoft Windows 95.x Retail Product
PROD/VER::
OPER/SYS:
KEYWORDS:kb3rdparty kberrmsg kbhw win95 kbHardware

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The information in this article applies to:

 - Microsoft Windows 95 
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SYMPTOMS
========

When you are using Windows 95 on a computer with a Cyrix processor and the
ACC2066 chip set by ACC MICRO, your computer may stop responding (hang)
unexpectedly, or you may receive an error message similar to the following
message on a blue screen:

   Fatal Error at 0028:c0027900 in vxd VFAT(01) + 000019d8

When you receive such an error message, the computer hangs. You may also
encounter random system hangs and random errors in programs.

CAUSE
=====

According to ACC MICRO, the ACC2066 chip set properly supports burst writes to
the processor, but it does not properly support burst writes back out. This
causes your computer to hang.

NOTE: The ACC2066 chip set is found primarily in laptop computers.

RESOLUTION
==========

If you do not know which type of processor is installed in your computer,
consult your computer documentation before proceeding. Do not perform the
following steps unless you are certain that your computer has a Cyrix processor
and that this is the problem.

Use the following steps to disable 16-byte write burst cycles:

1. Copy the Wb16off.exe file from disk 1 of your original Windows 95 disks or
   the Win95 folder on your Windows 95 CD-ROM to the Windows\System folder.

2. Use any text editor (such as Notepad) to open the Autoexec.bat file.

3. Add the following line as the first line in the Autoexec.bat file:

   c:\windows\system\wb16off.exe

4. Save and then close the Autoexec.bat file.

5. Restart your computer.

NOTE: Disabling 16-byte write burst cycles may result in a slight loss of
performance. This change in performance may not be noticeable.


Additional query words: crash winbook packet burst mode

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Keywords          : kb3rdparty kberrmsg kbhw win95 kbHardware 
Technology        : kbWin95search kbZNotKeyword3
Version           : :

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