Barry Watzman wrote:
> You are correct in that, at times, on some models (and, at times, on all
> models in the case of Compaq) they used a non-standard boot scheme with
> non-standard boot records.
>
> Compaq wanted to get around the fact that the "MBR" only allows 4
> partitions on a drive, period (which has been the case from the original
> IBM PC-XT in 1982 to this day).

I was not aware they had this in mind. To your knowledge, did they
manage to get more than 4 partitions on a drive? I do not know what
IBM's goal was; I'd be curious to know if Lenovo has continued this
practice.
>
> I'm not sure what IBM was doing, but I know that if you took a drive out
> of some IBM Thinkpads and put it into another machine, or if you took a
> drive formatted in a non-Thinkpad and put it into some Thinkpads, the
> drive geometry was not seen the same, and file and drive corruption
> would occur as a consequence.

I never experienced file corruption, because the drive cannot be
accessed in the standard way. Just at boot time, you get a geometry
error message and the machine does not boot. That is very frustrating
when you have to deal both with TP and "regular" laptop drives.

--
John Doue