NVMe BIOS Option ROM
What is it?
The NVMe BIOS Option ROM is a heavily modified version of iPXE, which can be integrated into a computers BIOS (or provided via a PCI card, USB flash drive, SD card, etc.).
It allows x86 computers to boot from NVMe devices attached via PCIe, even on devices which are much older than NVMe itself.
The NVMe implementation was ported from SeaBIOS and modified to work with iPXE.
The resulting Option ROM is only 23040 bytes (22.5 KiB!) large, so it will fit comfortably into any BIOS, flash chip or storage medium.
ThinkPad T43 booting Windows XP
ExpressCard/34 and /54
Commercially available adapters can adapt NVMe M.2 2242 SSDs into an ExpressCard/34 form factor:
These can be used in older devices like a ThinkPad T43, T410, T430.