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Q84302: Unable to Get into 386 Enhanced Mode with SCSIDISK.SYS

Article: Q84302
Product(s): Microsoft Windows 95.x Retail Product
Version(s): WINDOWS:3.1,3.11
Operating System(s): 
Keyword(s): 
Last Modified: 26-OCT-1999

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The information in this article applies to:

- Microsoft Windows versions 3.1, 3.11 
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SUMMARY
=======

IBM PS/2 computers equipped with the original IBM hard disk and a Procom MC
Enabler SCSI host adapter may have difficulty running Microsoft Windows version
3.1 in 386 enhanced mode.

If Windows 3.1 fails to run in 386 enhanced mode only when the device driver
SCSIDISK.SYS is being loaded, this problem can probably be resolved by disabling
the MC Enabler SCSI host adapter's direct memory access (DMA) settings.

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

According to Procom technical support, the following set of steps should be used
to reconfigure the PS/2's DMA settings.

1. Restart the computer from the IBM Reference disk. You must use a copy of the
  Reference disk that contains all of the proper Adapter Descriptor Files (ADF)
  for your machine. For more information on ADF files, please see the section
  below "ADF files".

2. From the Set Configuration menu, choose Change Configuration. Note the
  current settings under DMA Arbitration Level for both the Procom SCSI Enabler
  and the other hard disk in the system.

3. Swap the levels of both controllers. For example, if the MC Enabler is set to
  level 5 and the other hard disk in the system is at level 6, make the MC
  Enabler level 6 and the existing hard disk level 5.

ADF Files
---------

PS/2 machines come with a write-protected reference disk. In the main menu on
this disk, you are prompted to make a backup or working copy of the original
disk. This working copy will be customized for one machine.

Any time you add a new system card, such as the Procom's MC SCSI Enabler, the
card should come with a disk containing the proper ADF files for that card.

After installing the card you should boot the computer from the backup reference
disk. One of the options at the menu is to add ADF files to the working copy of
the IBM reference disk. Select the option to update the ADF files and follow the
instructions to copy the ADF files from the new disk that came with the card to
the working copy of the IBM reference disk. This will allow you to properly
configure the card for that particular machine with the new card installed.

For additional information, please contact Procom Technology technical support.

The Procom product included here is manufactured by a vendor independent of
Microsoft; we make no warranty, implied or otherwise, regarding this product's
performance or reliability.

Additional query words: 3.10 3.11 3rdparty

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Keywords          :  
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin310 kbWin311
Version           : WINDOWS:3.1,3.11

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