Yet a Windows update solved it, not a firmware flash. I'm still not sure if Windows update flashed the CPU. Maybe the update history can tell us?
But anyway, I mean the flashing target; i.e. if the firmware is flashed into the BIOS even tho it's called CPU firmware. I'm not aware that CPU's have ROM in them to accept a firmware.
Learn something new everyday, I guess. I'm off to look it up. Don't mind me, really.