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Hard Drive Limit for 386

Hi chaps

I didnt have a chance to try all the suggestions early this morning.

When I turn on the computer, it says the following;

Non system disk or disk eroor , replace and press any key when ready etc....


Put in my dos 6.22 boot disk which I got from the link provided here

Loaded up dos and tried the following:


fdisk

This confirmed that the hard drive was active however it was listing it as 127mb rather than 503mb

These are the details it lists:

Partition C:1
Status: A
PRI DOS
503MB
FAT 16
100% usage

I also typed in fdisk/mbr

In my BIOS, I have to set the hard drive type. On the 40mb one (hard drive I am replacing), it is type 17. On this one (504mb), googling it, I believed it was type 42. (maybe this is the issue). I can try each one until I get it right?

I only thought about the above issue after I thought maybe the HDD has error so I will format it.....

When I formatted it, it said the following:
Checking existing disk format
Existing disk format differs from that specified
Proceed (Y/N)

I left it formatted for the time being

Do I need to do the FDISK/MBR command before installing dos?
Should I try all the different hard drive types in BIOS and then use FDISK until the Hard drive size matches? (and then format the hard drive?)

Thanks for everyones help

I want to get the 540mb HDD working without using drive overlay

But I also have a 80GB ATA hard drive. The two smaller ones are AT (40mb) and (504mb). However the 80GB one is ATA - would this work withour any mods (apart from drive overlay).
 
Yes, you'll need to go through FDISK (but not with /MBR) and FORMAT before you put DOS on if the drive geometry changes from what's expected by the system BIOS.

You'll need to either use a version of DOS with FAT32 filesystem (DOS 7 or later) or a different OS such as Windows NT to make meaningful use of the 80GB drive.
 
Yes, you'll need to go through FDISK (but not with /MBR) and FORMAT before you put DOS on if the drive geometry changes from what's expected by the system BIOS.

You'll need to either use a version of DOS with FAT32 filesystem (DOS 7 or later) or a different OS such as Windows NT to make meaningful use of the 80GB drive.

Hi chuck the first thing I want to do is use the 504mb hdd without drive overlay. So im going to first do fdisk and then format the hard drive. The install dos as per normal. (format using FAT 16)

For the 80gb, assuming format hdd, then fdisk then drive overlay then dos? (format using FAT32)
 
I used on track disk manager in the end as it was a pain to set the correct hard drive settings in bios. I used the one set by the manufacturer but it did not like it. Thanks to everyone that replied.
 
Hi I have been looking up various sites etc on the hard drive limit fior 386 pc's.

Some say 504mb/512mb/528/540mb
Sorry for necroposting, but for historical reasons I wanted to indicate that 504MB is measuring a megabyte as 1000 kilobytes and 528 is measuring a megabyte as 1024kb or 1,048,576 bytes. These are BIOS limitations There are also various limits in different versions of DOS (which is my best guess for 512MB and 540MB). And different limitations for partition size with FAT. FAT12 and the original FAT16 could only use 32MB. FAT16b, first introduced in Compaq MS-DOS 3.31 and PC-DOS 4, can do 2GB partitions.
I don't want to get deeper into the weeds here now, suffice to say BIOS, various MS-DOS and PC-DOS version and various disk formats all have different disk size limitations. Be aware which ones you're running up against1
 
MS-DOS img’s are not free, but are widely available even localized versions, and FreeDOS is free and is localized ootb. Welcome to the future!

Only problem with FreeDOS is that it requires 6x 1.44MB floppies to install.

TechTangents recently put out a video on how to remove all the localizations and 386 support from FreeDOS and he managed to get it down to 4 360K img’s for his 5150 (before giving up on that idea and resorting to serial transfer.) So it is possible to get a FreeDOS install down to a couple of disks like MS-DOS if you are willing to roll your own.
 
The last version of MS Dos was four 1.44 floppies enhanced tools and the included supplement disk.. MSDos 6.21 was as well. 6 disks for FreeDos hardly a heart breaking chore. And it supports Fat 32..and a ton of useful utilities.

If you want a slim dos "vesion" with Fat 32 support the China Dos Union MSDos 7.1 may well be the way to go. Its install is only two 1.44meg floppies

This was all discussed on the old vf forums some 18 years ago. And Justin Webbers old computing.net foruns which is now part of Tom's Hardware. Has absolutely no ne taken any notes from those posts in allll this time?
 
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I don't think that those new to the hobby really care that images any old Dos versions from any major software house are "free" or not. They can get copies from all over the interwed. Of course there will be a small percenage which will search out and obtain the original media and manuals for completeness like I did decades ago before it became "interesting" again..

So being an "abandonware" Sheriff isn't really a good look, if you know what I mean.
 
5XX MB drives are the safest option but…

Occasionally there is a Mr Bios for your board which should expand it up to 1,2 or 8gb depending on the age of the bios.

Although rare some late 386 boards supported large mode for a 1gb limit.

So a DDO is not always required
 
5XX MB drives are the safest option but…

Occasionally there is a Mr Bios for your board which should expand it up to 1,2 or 8gb depending on the age of the bios.

Although rare some late 386 boards supported large mode for a 1gb limit.

So a DDO is not always required
Promise Enhanced IDE multi i/o card with support for up to around 8gig IDE hard drives or so can be used in 386 systems as well.

I've got one laying about in a box, with handbook, in a cardboard box out in the shed.
 
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Or, you could always use a SCSI drive and adapter (usually has its own BIOS).
That is exactly what my 386DX33 with 8megs of ram from 1989 had. SCSI/multi i/o card with fdd header along with serial and parallel ports. It was used in land surveying.
 
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