With Lenovo, the problem is that the BIOS has a whitelist of permitted PCI-Express cards and will refuse to boot with any unauthorized PCI card (source), i.e., they want you to buy only their own PCI cards. There are often ways around this, including hacking the BIOS, hacking the PCI-Express card (replacing the ID information). If you boot a non-whitelisted card your bios will throw the 1802 error,
1802: Unauthorized network card is plugged in - Power off and remove the miniPCI network card.
I suspect the same is true for HP.