This article was previously published under Q104354
SYMPTOMS
Dell 450M computers running Windows NT occasionally display a STOP message
with a Trap 0x0000007F (opcode 6) and Trap 0x0000000A.
MORE INFORMATION
Dell has confirmed that a problem exists with Dell 450Ms (BIOS revisions
including A08, A10, A11, and A12) with the 16 megabyte memory modules and
Windows NT.
Windows NT may trap occasionally with a Trap 0x0000007F (Unexpected Kernel
Mode Trap) with an opcode of 6 (illegal opcode) or trap 0x0000000A. The
traps appear to occur due to a BIOS problem on the Dell 450Ms. The problem
can be resolved by either slowing the machine down to a slower speed (16
MHz) or by doing the following.
To correct the BIOS problem on the Dell 450M, do the following:
Start the computer with an MS-DOS floppy disk with DEBUG.COM.
Run Debug and issue the following commands:
- o 28 2b
- i 24
(you will see a value of 11)
- o 28 2b
- o 24 31
Restart the computer by pressing CTRL+ALT+DEL. Do not power cycle
the computer.
This setting stays in effect until the computer is turned back on after
being turned off. At that time, you will need to perform the above steps
again. The above changes introduce a wait cycle and turn pipeline mode on
for the computer. There will be a slight performance degradation due to
doing this, but it shouldn't be a noticeable change.
NOTE: Dell is currently testing this fix and will provide a more
appropriate way of correcting this problem soon. No time frame is available
at this time. Contact Dell Computer Corp. for more information on this
issue.
The Dell products included here are manufactured by Dell Computer Corp., a
vendor independent of Microsoft; we make no warranty, implied or otherwise,
regarding these products' performance or reliability.