Sijmen 🧑‍💻

I set up a Windows 2000 VM in VMware, as one does, and now I'm trying to boot it with QEMU.

Turns out the CHS geometry set up by VMware is a bit unusual (56 sectors) and different from the QEMU defaults, and now Windows 2000 fails to boot.

So I tried to copy the geometry settings from VMware, but QEMU allows for only 16 heads - VMware used 255.

I guess I'm going to edit the partition table with a hex editor to update the CHS values according to QEMU's default geometry

#RetroComputing #Windows2000

Mar 14 at 8:55amWeb
Show threadKata 📎Mar 14
@sjmulder Did it work? Just updating this in the partition table? 🤔 (I remember other systems like OS/2 being annoying about this, spreading the CHS info to various places.)
Show threadSijmen 🧑‍💻Mar 14
@movq I got distracted so haven't tried yet, but I'll let you know. My hope is that 2000 is new enough to not care about CHS past the bootloader
Show threadSijmen 🧑‍💻Mar 16

@movq I've patched the MBR:

0x01BF: 00 39 00 (start CHS 0/0/63)
0x01C3: FE FF FF (end CHS 1023/254/63)

That got me a blinking cursor. I then patched the NTFS VBR:

0x7018: 3F 00 (63 sectors per track)
0x701A 10 00 (16 heads)

Now I get "A disk read error occurred", which is progress, but not what I hoped for!

Show threadKata 📎Mar 17

@sjmulder That’s about as far as I got with OS/2. 😅

How are you approaching this problem? I tried using QEMU + gdb but that’s pretty tough (at least for me) and I eventually gave up. 🥴

Show threadSijmen 🧑‍💻Mar 17
@movq probably not going to debug the boot code, not worth it. It's easy enough to do a fresh install