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The information in this article applies to:
- Microsoft Windows NT Workstation versions 3.5, 3.51, and 4.0
- Microsoft Windows NT Server versions 3.5, 3.51, and 4.0
- Microsoft Windows 95
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SYMPTOMS
========
When an Intel processor receives a specific invalid instruction, your
computer may stop responding (hang). Your computer must be turned off and
restarted to return to normal operation.
NOTE: Although there is no known operating system or application that
issues such an invalid instruction, you should be aware that a program can
be written maliciously to contain such an instruction. The operating system
would not trap this error, as it should, which results in the processor
hang.
CAUSE
=====
This problem can occur due to an error in the following Intel processors:
- Pentium processor
- Pentium processor with MMX technology
- Pentium OverDrive processor
- Pentium OverDrive processors with MMX technology
NOTE: This problem cannot occur on the following Intel processors:
- Pentium Pro processor
- Pentium II processor
- i486 and earlier processors
This problem is known as "Invalid Operand with Locked CMPXCHG8B
Instruction" and is erratum 81 on the Pentium processor errata list. For
more information, please contact Intel or go to the following Intel web
site:
http://support.intel.com/sites/support/
RESOLUTION
==========
Intel has identified a workaround to this problem that allows the operating
system to trap the invalid instruction and not pass it to the processor.
Microsoft has worked closely with Intel to provide the following hotfixes:
Windows NT 4.0
--------------
To resolve this problem for Windows NT 4.0, obtain the following fix or
wait for the next Windows NT service pack.
This fix should have the following time stamp:
11/24/97 12:24p 51,968 Hal.dll
11/24/97 12:24p 48,384 Hal486c.dll
11/24/97 12:25p 66,400 Halapic.dll
11/24/97 12:24p 46,112 Halast.dll
11/24/97 12:25p 82,208 Halcbus.dll
11/24/97 12:25p 80,320 Halcbusm.dll
11/24/97 12:24p 46,400 Halmca.dll
11/24/97 12:25p 68,544 Halmps.dll
11/24/97 12:25p 67,552 Halmpsm.dll
11/24/97 12:26p 79,008 Halncr.dll
11/24/97 12:25p 40,192 Haloli.dll
11/24/97 12:25p 56,608 Halsp.dll
11/24/97 12:25p 40,768 Halwyse7.dll
11/20/97 06:23p 938,816 Ntkrnlmp.exe
11/20/97 06:22p 918,848 Ntoskrnl.exe
This hotfix has been posted to the following Internet location:
ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/NT40/
hotfixes-postSP3/pent-fix/
NOTE: The above link is one path; it has been wrapped for readability.
Windows NT 3.51
---------------
To resolve this problem for Windows NT 3.51, obtain the following fix.
This fix should have the following time stamp:
11/24/97 12:42p 49,840 Hal.dll
11/24/97 12:42p 48,768 Hal486c.dll
11/24/97 12:42p 65,648 Halapic.dll
11/24/97 12:42p 46,704 Halast.dll
11/24/97 12:42p 81,056 Halcbus.dll
11/24/97 12:42p 79,200 Halcbusm.dll
11/24/97 12:42p 46,912 Halmca.dll
11/24/97 12:42p 67,696 Halmps.dll
11/24/97 12:42p 40,480 Haloli.dll
11/24/97 12:42p 53,744 Halsp.dll
11/24/97 12:42p 49,840 Halws3.dll
11/24/97 12:42p 41,072 Halwyse7.dll
11/21/97 01:35p 821,904 Ntkrnlmp.exe
11/21/97 01:34p 810,016 Ntoskrnl.exe
This hotfix has been posted to the following Internet location:
ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/NT351/
hotfixes-postSP5/pent-fix/
NOTE: The above link is one path; it has been wrapped for readability.
Windows 95
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A fix for Windows 95 is not yet available.
STATUS
======
Windows NT 4.0
--------------
Intel has confirmed this to be a problem in the Intel processors listed
above.
A supported fix is now available from Microsoft, but has not been fully
regression-tested and should be applied only to systems experiencing this
specific problem. Unless you are severely impacted by this specific
problem, Microsoft recommends that you wait for the next Service Pack that
contains this fix. Contact Microsoft Technical Support for more
information.
Windows NT 3.51
---------------
Intel has confirmed this to be a problem in the Intel processors listed
above. A supported fix is now available from Microsoft, but has not been
fully regression-tested and should be applied only to systems experiencing
this specific problem. Unless you are severely impacted by this specific
problem, Microsoft recommends that you wait for the next Service Pack that
contains this fix. Contact Microsoft Technical Support for more
information.
Windows 95
----------
Intel has confirmed this to be a problem in the Intel processors listed
above. Microsoft is researching this problem and will post new information
here in the Microsoft Knowledge Base as it becomes available.
Additional query words: 95 3.50 3.51 4.00 i386 malicious hangs freeze
freezes erratum cmpxchg8b compare and exchange 8 bytes cold boot hard boot
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