Hi Gerry,

> Could be a number of things, but in general you'd never put FreeDOS on a 
> RAID 5 partition of 140Gb.

Well, why not? Modern home PC mainboards already support RAID (not sure
if they do RAID 5, though) and the CHEAPEST (if you check the per-GB price)
harddisks today are IDE 160 GB ones.

> If you did not use a SCSI driver in your setup, it will depend on what 
> the BIOS wants you to see, and most BIOSs will only address the first 
> 8Gb. Strangely, Dell latest BIOS's seem to be able to address large SCSI 
> partitions without drivers, but I don't know how.

By supporting INT13 for the SCSI disks, of course. Basically every SCSI
BIOS can do that, otherwise you could not boot DOS from SCSI at all.
If the BIOS REALLY only supports 8 GB then it is a really bad BIOS, but
I think you only did not look carefully: 8 GB is the limit for all tools
which do not support LBA, or which fail to realize that LBA is supported
on the SCSI system. If you do have LBA support, the limit can be 32 GB
(popular Award 4.51 BIOS bug...), 128 GB (classic LBA communication
with the harddisk), 2 TB (2048 GB, limit of classic partition scheme,
also limit of FreeDOS), or 128 Exabytes (144*10^15, with the LBA48
communication method) or some insanely big value if you have a BIOS
which supports 2^64 sectors. As far as I remember, SCSI had two styles
of communications, one for up to 2^32 sectors (2 TB) and one for 2^64.

So until 2048 GB limit starts to hurt us, or until we want to plug
bigger disks without having to reboot, FreeDOS is ready for modern
harddisks. After that point, we have to support Dynamic Disks (some
as-usual badly-documented and MS-specific database thing which does
replace the MBR and classic partition scheme) and have to start using
64 bit values at some places, but I suggest to limit the size for each
single partition to 2048 GB to keep using 32bit at most places ;-).


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