"Formatting 1,951 M"

I think the issue might be the drive geometry.
386/486 era BIOSes usually had used CHS addressing and a 1024 cylinder limit.

So maximum values that could be used in CMOS Setup were 1023 cylinders (0-1023), 16 heads (or 15, if counted 0-15), 63 sectors. That's about ~500 MB.

Some 486 BIOSes also had support for E-CHS aka LARGE.
Merely late 486 BIOSes (WinBIOS etc) had LBA support.

This issue is even more of a problem with Windows 9x, btw.
Because it has two personalities.

The DOS personality uses whatever the BIOS uses.

The graphical part, though, uses a hsrd disk driver, which tries to determine real HDD drive geometry by asking the HDD itself (ATA command).

If two sides are different, data corruption and read/write errors may happen.

Ideally, Windows 9x realizes this and uses DOS as a HDD driver (HDD is being reported to be run in 16-Bit compatibility mode).

That being said, I think that the DOS side also had issues with the HDD parameters entered in CMOS Setup to begin with.

Probably it wasn't noticeable first, because the DOS installation was very small and didn't exceed the 1024 cylinder limit.

The partition size of 2GB as such is no issues. DOS can have four of those, I think. So up to 8 GB of storage capacity can be used fine.

It's just that the BIOS needs to support E-CHS or LBA.

It's not enough that the CMOS Setup let's someone enter certain values, the BIOS has to support them, too.
The CMOS Setup Utility is just a front-end, however, it doesn't know the actual limits of the BIOS.

Edit: To fix the issue, a Dynamic Drive Overlay (DDO) can be used. Like EZ-Drive.
It installs onto the hard disk in the boot sector and will make 286/386/486 PCs handle big HDDs.

Alternatively, XTIDE Universal BIOS can be used. It can be be burnt into an ROM chip.
A network card with a boot socket can then load the ROM during booting.

Edited.

Yes ! What size real hard drives and what size CF have you tried ? Anything 512Mb or less should be ok no matter the 486 board/bios.

Horun wrote on 2024-05-12, 23:50:

Yes ! What size real hard drives and what size CF have you tried ? Anything 512Mb or less should be ok no matter the 486 board/bios.

I have tried multiple sizes - 250mb, 425mb, 512mb, 1.9gb, 800mb....all do the same things. On the SD Card it was 425, 512, and 2gb. On the CF it was 1.9gb. On this current hard drive that crashed with the win95 installation, it was 250mb.

kaolinitedreams wrote on 2024-05-13, 00:04:

Horun wrote on 2024-05-12, 23:50:

Yes ! What size real hard drives and what size CF have you tried ? Anything 512Mb or less should be ok no matter the 486 board/bios.

I have tried multiple sizes - 250mb, 425mb, 512mb, 1.9gb, 800mb....all do the same things. On the SD Card it was 425, 512, and 2gb. On the CF it was 1.9gb. On this current hard drive that crashed with the win95 installation, it was 250mb.

It could be a related incompatibility, still. 286/386 and early 486 BIOSes did pre-date ATA-2 specification.
ATA-2 did change some subtle things, which caused all sorts of little issues.

In my case, it did hang a 286 PC during boot with a BIOS dated 1988.
Using XTIDE Universal BIOS on a network card fixed all issues. The electronics remained same.

So installing a DDO to HDD (easy to do, via setup floppy) or XTIDE Universal BIOS should should fix that as a side effect.

Phil's Computer Lab site has a collection of DDOs, I remember.
Trying them out doesn't cost anything, except a bit of free time. :)

[/quote]

It could be a related incompatibility, still. 286/386 and early 486 BIOSes did pre-date ATA-2 specification.
ATA-2 did change some subtle things, which caused all sorts of little issues.

In my case, it did hang a 286 PC during boot with a BIOS dated 1988.
Using XTIDE Universal BIOS on a network card fixed all issues. The electronics remained same.

So installing a DDO to HDD (easy to do, via setup floppy) or XTIDE Universal BIOS should should fix that as a side effect.

Phil's Computer Lab site has a collection of DDOs, I remember.
Trying them out doesn't cost anything, except a bit of free time. 😀
[/quote]

I'm not familiar with DDOs or XTIDE Universal BIOS (I'm still very much a newbie), but I will look into this. Thank you!

DDO + Dynamic Drive Overlay. Was a common way back then to allow use of a larger/newer HD than system supported. DrivePro, EzDrive, Disk Manager, MaxBlast...etc
Seems Phils page is down (blank) but here are some: http://www.vogonsdrivers.com/index.php?catid= … menustate=68,66
and some others: https://ia803408.us.archive.org/view_archive. … %20Hd_utils.zip
read any included TXT files before using any one of them. Generally you set your BIOS to drive type 1 (no matter what HD), save exit and install the DDO from floppy.
How they work is same but is sorta specific to each type.

Horun wrote on 2024-05-13, 01:05:

DDO + Dynamic Drive Overlay. Was a common way back then to allow use of a larger/newer HD than system supported. DrivePro, EzDri […]
Show full quote

DDO + Dynamic Drive Overlay. Was a common way back then to allow use of a larger/newer HD than system supported. DrivePro, EzDrive, Disk Manager, MaxBlast...etc
Seems Phils page is down (blank) but here are some: http://www.vogonsdrivers.com/index.php?catid= … menustate=68,66
and some others: https://ia803408.us.archive.org/view_archive. … %20Hd_utils.zip
read any included TXT files before using any one of them. Generally you set your BIOS to drive type 1 (no matter what HD), save exit and install the DDO from floppy.
How they work is same but is sorta specific to each type.

The last time I used OnTrack 9.57 I'm pretty sure it said to set BIOS to Type 22.