Are you aware you can press F8 during normal bootup and select "Command prompt only"? Unlike "Restart in MS-DOS mode", the resulting environment is indistinguishable from what you can get with a boot disk. You can even include what you need in autoexec.bat and config.sys. (Of course everything in autoexec.bat and config.sys will also load when you boot Windows normally, but Windows will generally ignore whatever gets loaded that way.)

Anyway, if there's anything unusual on your rescue disk, it would be right there in the floppy's autoexec.bat and config.sys – it won't magically "set up caching" somehow independently of whatever is in there.

I was aware of that 😀 but I wasn't sure what would be loaded and what wouldn't. I have a faint memory of things like mouse.com having an effect on Windows 98 when left in the autoexec, so I didn't want to worry what sbeinit or a network packet driver would do. This way seemed cleaner (and less likely to leave me with an unbootable computer if I mess up). (Plus those precious seconds loading a large soundfont on every boot!) thanks for the advice.

MrD wrote on 2021-05-06, 04:45:

I have a faint memory of things like mouse.com having an effect on Windows 98 when left in the autoexec, so I didn't want to worry what sbeinit or a network packet driver would do.

To be quite clear, there's nothing special about autoexec.bat: you can select "Command prompt only" and then manually run everything you would normally run via autoexec.bat, or even put those commands in a separate .bat file. It's really only config.sys you need to worry about – and even then there are lots of ways to load device drivers from a command line, as in How to load DOS device drivers from the command line? . (Some things like EMM386 do need to be loaded in config.sys, but like I said, Windows is at least sufficiently intelligent to shut down EMM386 when it is loaded in config.sys.)

Anyway, what motherboard are you using? There are tales told of VIA chipsets that specifically have severe compatibility problems with PCI Sound Blaster cards. https://forums.anandtech.com/threads/any-deta … sb-live.554934/ is the best reference I could find with some Googling.

MrD wrote on 2021-05-06, 01:50:

I noticed that Win 98 itself was running Scandisk every time I restarted the computer without my boot floppy inserted. I put it down to Win98 being weird - I had been installing and removing a lot of drivers, and moved my PCI cards around a few times.

This would be my 1st sign of concern, sounds like Windows is detecting something isn't quite right.
Not saying it's the most reliable sign. It doesn't take much to break Windows shutdown routine forcing scandisk next boot but even still.

If you run a full scandisk test does it find anything?
What did you use to partition the HDD? the empty folders messed up file names are typical signs of file corruption due to incorrect cluster size or the like.

Re Rebooting
As long as you see the post screen when rebooting then you can be sure memory has been cleared. Doesn't matter if this is done via Windows shortcut, F8 Menu, Boot disk. You still end up with a clean slate and only the items in that methods start-up files will be loaded.

Anyway, what motherboard are you using?

An atrocious MS-6534 from a Medion cheapo supermarket pc from 2000. The bios menu has a strange bug where when you cycle through the 'Halt on: All Errors/No Errors/Keyboard' option, sometimes random colours appear and the screen shifts up by a row of characters, but just that one option. It's bizarre.

This would be my 1st sign of concern, sounds like Windows is detecting something isn't quite right.
Not saying it's the most reliable sign. It doesn't take much to break Windows shutdown routine forcing scandisk next boot but even still.

Before I started using the boot disk, and I was just booting (and rebooting) into Win98 to install the drivers for the Voodoo3, then SB Live, then network interface, it seemed perfectly solid.

If you run a full scandisk test does it find anything?
What did you use to partition the HDD? the empty folders messed up file names are typical signs of file corruption due to incorrect cluster size or the like.

The on-boot scandisk shows a grey dialog briefly saying it's looking for crosslinked files, but it doesn't say it's found some. (IIRC it would usually give a report and offer to save the log if it sound something anomalous?)

I booted from a Gparted livecd with Gsmartcontrol and the long SMART test didn't find any errors. I'm running scandisk now.

It was a while ago but I'm fairly certain I partitioned it (2x 20gb fat32) using the fdisk from a Win98 boot disk.

Re Rebooting
As long as you see the post screen when rebooting then you can be sure memory has been cleared. Doesn't matter if this is done via Windows shortcut, F8 Menu, Boot disk. You still end up with a clean slate and only the items in that methods start-up files will be loaded.

Yes 😀 I'm not worried about things persisting over a reboot, as long as it is a full reboot.

ah the order you installed the drivers may explain scandisks appearance. Nothing wrong with the order just that networking was last.
I've got 9x PC's that don't like shutting down with active network connections, shutdown patches don't help. but as I only turn on the switch when needed most times its a non issue. Good old reliable 9x.
And yeh scandisk at boot will let you know if it finds anything or just carry on as normal if nothing is found.

I wouldn't have expected any results form the SMART test as that's hardware level and I suspect its software or more specifically the way the drives been setup but even that I'm not so sure now.
fdisk is pretty basic but that works in your favour as it doesn't support anything windows can't

An older PC I'd possibly blame dodgy addressing by the BIOS setup, but your motherboard s based the i845 chipset, about as late as IDE goes on Intel chips.
Maybe the funny halt on keyboard issue is a sign the motherboard is starting to die and something related to IDE is also bugging out? That's just pure guess though.

If it was me I'd fidsk the thing again just to be sure, but I also wouldn't give it more then a 10% chance of working

Having fdisked and surface scanned the hard drive and found no problems, I think I'm going to put this weird behaviour down to moving the PCI cards about and rebooting windows.