32-bit disk access on 755 (fwd)

[Adam Wilkinson <adam@tiamat.umd.umich.edu>]

The IDE spec only allows drives < 512MB. The ThinkPad BIOS adds support 
for > 512MB, which allows the drive to be accessed. However, 32-bot disk 
access circumvents the BIOS, therefore Windows can;t understand your drive.

CONCLUSION: You can't use 32-bit disk access on ThinkPads with > 512MB 
drives.

--
Adam Lee Wilkinson          * Just remember, no matter where you go,
adam@tiamat.umd.umich.edu   * there you are!   
Compuserve: 75470,71        *                 - Buckaroo Bonzai

---------- Forwarded message ----------
Date: Thu, 13 Oct 94 09:28:09 PDT
From: Robert George <george@cs.nps.navy.mil>
To: tp750@CS.UTK.EDU
Subject: 32-bit disk access on 755


I just purchased a ThinkPad 750C which had a smaller drive (170MB) replaced
with a Sigma Data 540MB replacement.  This swap was done at IBM (Federal
Sales) suggestion.  IBM fully supports this drive, and the warranty remains
intact.  The person I spoke to at IBM thinks that the Sigma Data is
probably the OEM drive that is delivered in the 75x's.

The problem I'm frustrated with, is that according to the 75x FAQ, 32-bit
disk acesses should work on the ThinkPad with WFW 3.11.  However, when
I turn on 32-bit disk acesses in the 386 enhanced menu, I get the following
error when Windows reboots:

The Microsoft Windows 32-bit driver (WDCTRL)
validation failed at phase 07, 1F

To continue starting Windows without using the 32-bit
disk driver, press any key 

Has anyone successfully used 32-bit disk acess on the 755's?   Is it possible
that I new a BIOS update? (I have 1.07).  Is it possible that something
that Sigma Data is doing is incompatible with 32-bit disk acesses?

Thanks,

Robert George
(george@cs.nps.navy.mil)