Hmmm, this stumped me for a while. Your argument makes complete sense, but then why do I need drivers for my OS to access the NIC, when it should be able to use

Hmmm, this stumped me for a while. Your argument makes complete sense, but then why do I need drivers for my OS to access the NIC, when it should be able to use the same API exposed to BIOS? So I looked it up: https://en.wikipedia.org/wiki/Preboot_Execution_Environment https://en.wikipedia.org/wiki/Preboot_Execution_Environment It's fairly light on details, but my interpretation is that for a NIC to support PXE boot it has to have firmware that exposes a standardized API so that the boot loader can functions as a DHCP client and a TFTP client. As far as I can tell, the NIC doesn't have to provide some standardized method for general access, just those two things. The NIC could even have a completely different, completely separate API that it expects the OS to use, and just has some firmware that acts as a shim to expose to the boot loader the PXE client API. Assuming this is true, Intel ME could access the NIC using the PXE boot API, but this only gives it the ability to act as a DHCP client and TFTP client, not arbitrary networking operations. I could be completely wrong about that, though. This is, at best, an educated guess.