m.2 NVMe not recognized during Windows 10 installation

@beemo999  AHCI is easier since RAID mode can sometimes require that you provide the Intel Rapid Storage driver. What happens when you get to the step asking where you want to install Windows, immediately after choosing a Custom installation rather than an Upgrade? Is there truly no disk or partition set listed at all?  That’s very unusual because AHCI exposes the native storage interface to the OS, and Windows has had native NVMe support since Windows 8. You can try opening Command Prompt by pressing Shift+F10 and then running diskpart and entering “list disk” to see what the system detects. If you don’t see a disk there, normally I would think that the disk isn’t being detected by the system firmware either, except that you say Ubuntu currently boots as expected from this SSD? If you can successfully boot Ubuntu but can’t even get the disk to be detected by diskpart in Windows 10 Setup, I’m not sure what to suggest.

But on a side note, you forgot to mention the model of your system. The BIOS version isn’t all that helpful if the system model isn’t indicated. :). In fairness, that shouldn’t matter for this particular issue based on what you’ve described thus far, but just for future reference.

This worked on a Dell 3020. Small Bios hack or driver you can do from SSD prior to dropping NVMe M.2 in slot.

https://www.tachytelic.net/2021/12/dell-optiplex-7020-nvme-ssd/?amp

128000 Ram.

CrystalDiskMark showing close to 1600 MB/s which is not bad for an old garbage clunker.