I have a Lenovo G580 laptop, and I'm running Windows 10. I've noticed that the fan on my laptop doesn't always do its job. There have been several times that I've noticed it being very hot, and the fan wasn't on. I reset the computer, but it didn't help. Usually, I have to turn off the computer, leave it off for at least 30 seconds, and then turn it back on to get the fan to work. This only happens intermittently, but it worries me when I have to leave it on for an extended period of time to let it finish a task. Any ideas?