At some point my fan completely stopped working. Either the hardware failed without making any weird sounds, or a BIOS update killed it without me noticing. It definitely didn't work on version 30 and still doesn't on version 33. I've reset the BIOS to default values and still get no response, no sound or movement at all. I've tried downgrading but the updates fail. I've disassembled the thing but there is nothing visibly wrong and it's still plugged in.
Am I missing something? Is there a known problem with this? Can I order a replacement?