The fan/temp control in the unlocked BIOS doesn't work for me on my y580. Tried setting the fan to 100% at low/high thresholds and nothing is affected. I have a system board that is flaking out and I think it is due to chronic overheating (began having problems at 1 year). Maybe I'll be able to manually hardwire the fan to run at full speed before replacing the system board. BTW my issue is that my y580 hard locks (have to hold the power button in to shut it down when it locks) during normal use and actually performs more reliably when playing a game. I believe this is because of an issue with the Intel Graphics chip caused by ongoing heat stress (hence the desire for increased fan speed).
