[rwmj]

You might want to experiment yourself before making bold assertions, because you are wrong. I've just tried these (with qemu-system-x86-6.0.0-7.fc35.x86_64):

• Microsoft_Windows_NT_Server_Version_4.0_227-075-385_CD-KEY_419-1343253_1996.iso (1996, own copy)

Installer starts, locks up with screen corruption about 5 seconds in.

• https://archive.org/details/windows-95_fixcpu_iso_windows_is... (1994-ish)

Cannot read the emulated CD-ROM.

• https://archive.org/details/redhat-9.0_release (2003)

Installer boots, but fails at partitioning stage, the first time it accesses the disk.

• https://archive.org/details/IBMOS2Warp4Collection (1996)

Cannot read the emulated CD-ROM.

• Plan 9, 4th ed. (2003, own copy)

Gets quite far, up to the login, although with a lot of errors, but later hangs hard. (Out of all of them this looks closest to being possible to make work.)

I can also tell you that we're moving away from emulating i440fx entirely (to q35), and nothing prior to 2005 will work once that change has been made. In addition, changes to how virtio works means that guests before about 2010 that use virtio will have problems unless you take special steps.

[anthk]

Ah, sure?

1) Don't use Qemu from the kvm binary.

2) Don't use VirtIO

3) Don't set the CPU higher than a Pentium for w95/w98/NT4, Pentium2 may be fine for w98SE.

   >qemu-system-i386  -M help 
   isapc                ISA-only PC

   >qemu-system-i386  --version
   QEMU emulator version 6.1.0
   Copyright (c) 2003-2021 Fabrice Bellard and the QEMU Project developers

This should work for NT4

   qemu-system-i386 -cdrom $CDROM -m 32 -vga cirrus -net nic,model=pcnet -net user -cpu pentium -hda $DISK

Also, if qemu enables kvm by default, set the machine acceleration method to TCG.

Bye, "virt engineer".

[fomine3]

What's your parameter for Qemu?

Could you provide link to discussion that i440fx going to be removed?

[anthk]

Nah, he is a "virt engineer", ofc he/she doesn't have a clue on Qemu without KVM ;).

JK. Old stuff it's difficult to emulate if you only know qemu from KVM and you didn't use Qemu since the Bellard days, or Bochs.

Meanwhile, I emulated w95, w98, Linux 2.2/2.4 based distros (my first Linux), OS/2 and so on just fine. Even BeOS.

[lokedhs]

I installed NT 3.51 in Qemu not long ago. I can look up the Qemu settings I used if it's of interest.