DM> Wasn't there a 30 or 40meg limit in the days of DOS-only systems?

Yes, DOS 3.3 and earlier had a 32MB limit per partition
and 3.2 and earlier only allowed one of those as well.

DM> Could have been a limitation of the DOS itself,

Yes.

DM> and DM was used to partition the HDD to get around that.

Yep. Or more strictly it has its own partition design which didnt
have that limit that the DOS FAT-12 which imposed that 32MB limit did.

DM> I wouldn't use DM myself these days - there are more elegant solutions.

Depends on the version, the latest one isnt too bad itself. There isnt
a whole lot in it with the range of about 5 of them you commonly see.

DM> What about Win95 ? Is it still stuck with the
DM> 540k limitation if LBA or LARGE is not enabled ?

Yeah, that doesnt change with Win95, same limits apply.
There is also a 2GB limit per partition as well.
@EOT:

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