Computer May Hang with Cyrix Processor and ACC2066 Chip Set (134295)

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:

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.
Use any text editor (such as Notepad) to open the Autoexec.bat file.
Add the following line as the first line in the Autoexec.bat file:
c:\windows\system\wb16off.exe
Save and then close the Autoexec.bat file.
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.