Let's run Win10 on really really old hardware

I'm afraid you are stuck with Windows 7 32-bit. Even if CPU supports PAE/NX, it must be also supported by the motherboard and enabled in BIOS, rather unlikely for a Pentium M laptop. Besides chances are there is no WDDM driver for the graphics anyway, so you must install Windows 7 32-bit in order to use the Windows XP driver (XPDM). Even if you could enable PAE/NX to install Windows 10 32-bit without WDDM drivers you would use Microsoft Basic Adapter (software only, no acceleration) and would be too slow, definitely doesn't worth your effort.

Well, still managing to get the latest Release Preview 18362.53 running on the old Acer Travelmate 2423 with Celeron M 370 1.50 GHz, 2GB DDR2 with a BIOS dating back to May 2006.

It is currently multibooting with 1607 and 1809 1607 has reached end of life now on Pro and Enterprise/Education, and was the last version that could be installed with an upgrade from Windows 7 on this machine.
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However it will not clean install, upgrade via Windows update, or from any downloaded Windows version update iso since 1607, 14393, the Anniversary Update.

It may still be possible to apply the Windows Image (\sources\install.wim) using DISM or Imagex to this old machine's main storage, but that takes an age and is not always successful, especially with failures during OOBE, but there's an easier and more reliable way to do it.

It involves creating a windows installation on a more modern machine, but inside a native-booting VHD. 40GB is a good size to use I find. Any user modifications and programs may be installed here, as well as any cumulative updates, etc., that there may be available.

In order to make a 40GB VHD easily transported either by portable storage or over a network, it can be zipped down to a zipfile little more than 3 GB in size, then re-extracted. Extraction takes about 30 minutes on the Travelmate. This can be extracted directly to the main storage of the Travelmate where space is limited.

Once the VHD has been mounted on the Travelmate, say in a drive V:, using bcdboot V:\windows to make a boot entry on the Travelmate BCD.

On rebooting, there is an error bluescreen - your computer needs to be repaired..., but on the second reboot, it enters a windows update blue dialog with the circling dots, downloads some stuff, then rapidly sets up devices etc after changing to a black screen.

Finally it brings up the lock screen and allows me to log-on, then the welcome screen. Finally, after a visit to Device Manager, and disabling some devices that have warnings, which have never been recognised correctly or installed in every Windows 10 version run on this machine, the machine is ready for a final reboot with everything I need working, and at a reasonable speed.

However I then checked Activation, which had deactivated because of the settings it carried over from the initial installation on the other machine. I just needed to check the other Windows 10 installations on the Travelmate for a copy of GenuineTicket.xml from running GatherOSState.exe on the 1607, which I keep just for instances such as this, to add to the clipserver genuineticket folder. However, this is the first time that I remember having a transferred system to a machine that has already been activated not activating within minutes, but I think that the activation servers must be extra busy at the moment.

It works perfectly adequately with desktop applications in multitasking mode, despite the low processor and memory specifications. Next stop - skippy...:)

All motherboards are different. With the Travelmate, the cut down BIOS, and the lack of working chipset, graphics and device drivers create a PNP hell for setup and Windows 10 duplicates many devices when "getting devices ready".

Here is my Device manager in 1903, with many of the duplicated devices disabled. Where there are still devices showing yellow triangle warnings, these cause BSODs if I disable them.

In the earliest Windows 10 version that I could run,1511 on this machine, the memory conflicts caused system interrupts that would cripple the machine using 100% CPU, and filling the memory up until I managed to disable the Modem, network adapters, and the Video controllers.



With 1903, the system runs faster and much more responsively than with any earlier version I have tried. Whereas 1511 was crippled, 1607 worked acceptably with the Yellow warnings, but better with them disabled where possible. No, I couldn't install 1709, @bobjoe it would fail during OOBE. I had to apply it with the Install.wim.

Just like Windows itself having problems with the lack of drivers, and conflicting devices, I think that the Windows 10 Preinstallation environment, which uses a ramdisk and more memory for graphics and as system memory, and some features of setup just run out of steam.

All my (old) laptops seem to default to "DESKTOP-whatever" perhaps Windows 10 has a database of modern PCs, but doesn't bother about older models - I cannot say.