DOCUMENT:Q156492  25-MAR-2002  [win95x]
TITLE   :GP Fault or Fatal Exception Error on Intel MMX CPU
PRODUCT :Microsoft Windows 95.x Retail Product
PROD/VER::
OPER/SYS:
KEYWORDS:kbhw win95 kbHardwarekbfixlist

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The information in this article applies to:

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

When you are running a program or using a device driver that calls MMX- specific
instructions in the retail release of Windows 95 on a system with an Intel
processor supporting the MMX instruction set, the following symptoms may occur:

 - A general protection (GP) fault error message

 - A fatal exception error message on a blue screen

This problem does not occur with Windows 95 OEM Service Release 2 or later.

CAUSE
=====

The retail release of Windows 95 does not properly support some MMX instructions
if they are called from a device driver or from program code running in
protection level 0 (Ring 0, also known as privileged or Kernel mode). If these
instructions are issued while the processor is operating in Ring 0, a GP fault
or other serious error may occur.

RESOLUTION
==========


STATUS
======

This problem no longer occurs in Windows 98. To resolve this problem, install
the current version of Windows. For information about the current version of
Windows, visit http://www.microsoft.com/windows.

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


Additional query words: gpf

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Keywords          : kbhw win95 kbHardware kbfixlist
Technology        : kbWin95search kbZNotKeyword3
Version           : :
Issue type        : kbprb

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