Anyone? 🫥

What C/H/S values does the SSD report? On my CF card installs the drive reports only 16 cylinders. This means the c/h/s limit for the CF card is 504MB (16/1024/63). I create a partition at the beginning of the drive of 480MB and install to that. Once patched with SP6 and the XP ntldr/ntdetect.com I can use lba, so capture with ghost and restore to a bigger partition.

The installer is limited to C/H/S even with the updated atapi.sys, it just means you might see the whole drive, but you cannot use it until SP6 is installed and the later bootloader from 2000/XP to allow loading files with lba. I'm assuming this is using some sort of disk controller card? NT4 does not support AHCI and SATA controllers will need to be used with NT4 setup drivers (so probably scsi or SATA1 only).

The motherboard is set up with the controller in IDE mode (in fact, it works even on Win98 without special drivers)

I need to figure out how to read C\H\S from the SSD, or can I trivially make an even smaller FAT partition?

You could just try with 480MB NTFS as that should cover most things. The bootloader and OS files have to remain within the C/H/S limit until patched, otherwise NT will be unable to access the Windows files required to boot.

Thank you, I will try in a few minutes

I'm trying with the smallest HDD I have (120gb), but nothing, when starting SETUP I have the error visible here. I made a single 480MB partition using FDISK of the Windows95 A floppy

Tonight I will try via linux DD to reformat the hard disk by filling it with "0", so as to remove all traces of anything that may give problems

Instead I tried using this ISO of NT4 with SP6 integrated, the boot device error disappears, but I have another one on the video card, ideas for that?

I've not tried NT on anything modern other than VMs (before recent CPUs became a problem).

Stop 7b will be missing/broken storage controller drivers, have you tried the UniATA driver as an additional driver instead of the SP4 ATAPI one? I found it ok, but I'm only using it on a PIII which I felt even that was a bit late for good NT4 compatibility!

What card are you using for graphics output? NT doesn't even understand AGP properly although it works.

I bypassed a few problems. Installed a vm with nt4 and sp6. then via DD in Linux I wrote the virtual disk to a physical disk.

I booted NT in VGA mode and then installed the Nvidia drivers.