My new system is a Lenovo M700 (an industrial small form factor PC). It has an American Megatrends BIOS. But there is no option in the BIOS to disable Bluetooth (or WiFi). I think the hardware for both are on one Intel card.
You FAQ says I should disable the bluetooth adapter. But I could just remove the card, but I still need wifi, so that won’t work for me.
BTW, the reason I’m doing this is because I snapped the antenna lead for bluetooth adding an M2 SSD and a new disk drive. I was uncomfortable soldering on the board, so thought a USB bluetooth dongle would be the safest approach.