I'm writing this on a laptop which has all video outputs on Nvidia GPU and Intel's card is disabled completely in BIOS by vendor (Lenovo Y500). AMD had Switchab

I'm writing this on a laptop which has all video outputs on Nvidia GPU and Intel's card is disabled completely in BIOS by vendor (Lenovo Y500). AMD had Switchable Graphics which had the same architecture choice as Optimus (MUX-less pain in the ass), but IIRC they've dropped it.