There's all kinds of BS on Google search of how to do this and none of it works. One even said to toggle it off and on by pressing the Function key and F6 or F7. I almost wore those keys out trying to do this.
For some reason tonight I got a notion to try Alt F6, low and behold it works and toggles off and on with a Gateway laptop using windows 8.1

Hope this helps some lost soul about to lose their mind.