What does HackerNews think of ntvdmx64?

Microsoft's backwards compatibility is insane | Aug 2023

There's a "pirate" port of NTVDM to 64-bit Windows (from leaked NT 4.0 source) so it's certainly not technically infeasible: https://github.com/leecher1337/ntvdmx64

Revisiting Borland Turbo C/C++, A Great IDE back in the 90s – CodeProject | Apr 2023

The link in the post to NTVDMx64 at Columbia seems to be broken, but the associated GitHub project appears to be at https://github.com/leecher1337/ntvdmx64

  "What is it?
  ===========
  NTVDMx64 is a port of the well-known Windows NTVDM, which is used by windows 
  to run DOS-Applications, to 64bit Windows, so that you can run your 
  DOS-Applications on 64bit Windows too."

Something I had wanted and didn't know existed!

Alt-Enter Doesn't Window DOS Graphics in XP (Used to Work in NT and W2K) (2006) | Dec 2022

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People who absolutely need to run 16-bit DOS apps on x64 Windows can use NTVDMx64: https://github.com/leecher1337/ntvdmx64

State of the Windows: How many layers of UI inconsistencies are in Windows 10? | Jun 2021

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Not natively, but ntvdmx64[0][1] and otvdm[2]/winevdm[3] work fine, albeit a bit slowly.

[0]: http://www.columbia.edu/~em36/ntvdmx64.html

[1]: https://github.com/leecher1337/ntvdmx64

[2]: http://www.columbia.edu/~em36/otvdm.html

[3]: https://github.com/otya128/winevdm

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For those interested, Wikipedia says there's no native/builtin 64bit NTVDM due to

> In an x86-64 CPU, virtual 8086 mode is available as a sub-mode only in its legacy mode (for running 16- and 32-bit operating systems), not in the native 64-bit long mode.

...

> The NTVDM is not supported on x86-64 editions of Windows,[31] including DOS programs,[32] because NTVDM uses VM86 CPU mode instead of the Local Descriptor Table in order to enable 16‑bits segment required for addressing[33] and AArch64 because Microsoft did not release a full emulator for this incompatible instruction set like it did on previous incompatible architecture.

https://en.wikipedia.org/wiki/Virtual_DOS_machine#Windows_NT...

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Personally, since Microsoft still releases 32bit builds of Windows 10, I just dual boot 32bit (~48GB)/64bit (~900GB) partitions and run the 16bit programs natively on an old Thinkpad.

Initial preview of GUI app support for the Windows Subsystem for Linux | Apr 2021

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Try winevdm[1] or ntvdmx64[2], which I believe is based on leaked Microsoft source code. I've successfully gotten Tetris running on win10x64, and I'm happy enough with not needing dosbox+win3x for it.

1: https://github.com/otya128/winevdm 2: https://github.com/leecher1337/ntvdmx64

I still use WordPerfect 6.2 for DOS | Sep 2020

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Well it's here, but you probably have to join the group to get access:

https://groups.io/g/dosOrCAD/files/OrCAD%20driver%20without%...

I put a copy in one of my github repositories:

https://github.com/jhallen/joes-sandbox/blob/master/pcb/orca...

I think this is a description of what's going on:

https://airborn.com.au/layout/vddtest.html

Well this is getting really off topic, but it appears that you can run DOS programs in 64-bit Windows 10:

http://www.columbia.edu/~em36/ntvdmx64.html

https://github.com/leecher1337/ntvdmx64