Stuck iPXE initialising devices - .efi pxe boot

[NiKiZe]

You can find officially built versions on boot.ipxe.org try to use the efi.ipxe from there, I'm expecting you got get the same issue with the hang. And then try snponly.efi instead, you should hopefully get further, and you should be able to press Ctrl-B (or ESC-B if your firmware is buggy) to get into the iPXE shell and test things out, network might however not work with snponly depending on how much Grub destroy things.

It would also be a good idea to test booting ipxe.efi without first booting into grub.

These steps is to figure out a baseline and see what the actual issue is. But already it is somewhere between hardware/firmware, Grub or iPXE since you don't even get to wimboot.