Dual-booting NT 3.51 and NT 4.0

[Goldfish64]

I've decided to rebuild this machine, but I've encountered a strange issue: if I install NT 3.51 and then NT 4.0 together, NT 3.51 will no longer start, crashing during boot with a 0x7B (INACCESSIBLE_BOOT_DEVICE) BSOD. If I copy 3.51's NTLDR and NTDETECT.COM over the NT4 ones, NT 3.51 boots successfully but NT4 no longer boots, which is expected. I've done this before, except now with a bigger drive, and haven't found anything online, so I'm wondering if NT doesn't like drive overlays. Not sure if this is related, but the NT4 SP6a installer BSODs with a UNEXPECTED_KERNEL_MODE_TRAP right after file extraction. NT 3.51 has SP5 installed.

Currently, both NT installs are on the same FAT16 partition that is ~950 MB in size, so that eliminates any large disk issues. If I remove the drive overlay, DOS 6.22 and both NTs should work just fine, but would a future 98 SE that is above the 8 GB boundary still work? I would assume it would, seeing as 98SE doesn't use the BIOS for disk access.

EDIT: Got rid of the overlay but now the Windows ME boot disk fails to recognize above 8 GB. Guess it needs to stay.

EDIT2: Using the UniATA driver instead of the inbox driver solved the issue in Windows NT 3.51. Don't exactly know why, but I'm guessing it has something to do with NT 3.51 not supporting above 8GB disks even though it was installed within the first 8GB.

[os2fan2]

When you dual boot NT 3.51 / 4.0 / 5.0+, you have to take to account that NTFS has changed.

NT 3,51 should be installed on a fat c: partition. This is because 4.0 and 5.0 change the fat that 3.5x can no longer read it.

NT 4.0 and 5.0 can be installed in different partitions, but 5.0 changes the 4,0 partition type, and NT 4 can not then boot with 2000 installed. Google for NTFS NT4 and you should see what is needed to run NT4 and NT5 successfully.

NT 5.1 change the structure of the partition by moving the partition root-files further in the partition, but 5.1 and 5.0 are essentially the same elsewise.

Neither 3.51 nor 4.00 can boot off a fat32 partition.

[Goldfish64]

When you dual boot NT 3.51 / 4.0 / 5.0+, you have to take to account that NTFS has changed.

NT 3,51 should be installed on a fat c: partition. This is because 4.0 and 5.0 change the fat that 3.5x can no longer read it.

NT 4.0 and 5.0 can be installed in different partitions, but 5.0 changes the 4,0 partition type, and NT 4 can not then boot with 2000 installed. Google for NTFS NT4 and you should see what is needed to run NT4 and NT5 successfully.

NT 5.1 change the structure of the partition by moving the partition root-files further in the partition, but 5.1 and 5.0 are essentially the same elsewise.

Neither 3.51 nor 4.00 can boot off a fat32 partition.

Don't think it is a filesystem issue. I don't have Windows 2000 or newer in the mix, only NT 3.51 and NT 4.0. Both are currently installed on a FAT partition. I noted that I had this exact same setup that worked fine except there was no drive overlay, leading me to think that might be the issue.

[os2fan2]

If you be using a 950 MB fat partition, ye may be running into the 504 MB bios problem. ntfs 4 uses the system bios to boot, and then must load itself from somewhere under the 504 mb. I had this problem in RL on my 486dx66, which had two 1 g drives, but neither OS/2 nor NT4 would boot in a partition that went over the 504 boundary.

I've dualbooted nt3.51 and 4.00, but i put them into successful partitions, because of the various hidden files etc in the OS partition, i believe. None the same, there are indeed issues between ntfs3/ntfs4/ntfs5 and ye need to do things to mark partitions if you have an OS with ntfs4 or ntfs5 present.

I never tried booting nt3 off this system, because it came later.

[Goldfish64]

If you be using a 950 MB fat partition, ye may be running into the 504 MB bios problem. ntfs 4 uses the system bios to boot, and then must load itself from somewhere under the 504 mb. I had this problem in RL on my 486dx66, which had two 1 g drives, but neither OS/2 nor NT4 would boot in a partition that went over the 504 boundary.

I think this machine is too new to suffer from that limit (it's a Pentium MMX system). The only limit I'm aware of is the 8 GB limit, both at the BIOS level and with Windows NT. In this case, everything is within the first 8 GB of the disk, so no issues there.

EDIT: I might have found the solution. If the UniATA driver is used instead of the inbox driver in Windows NT 3.51, NT 3.51 boots successfully while using the NT4 boot loader and is also able to recognize the entire 80GB disk. This is using the OnTrack Disk Manager drive overlay as that is needed for DOS/98SE.