night_wolf_in :
it depends on ur mobo. some mobo's bios have "smart fan" that will stop when the cpu is not hot, or cpu not in load.
That would be my guess. Good Old Smart Fan. But the real question is.... Is it really that smart?
Smart Fan: Is it 35C yet?
Bios: Nope
Smart Fan: Is it 35C yet?
Bios: Nope
Smart Fan: Is it 35C yet?
Bios: Nope
Smart Fan: Is it 35C yet?
Bios: Nope
Bios: Psst... its 36C now.
Smart Fan: DoH!! Where's that start button....
Smart Fan: Okay its running now.
Bios: Its 34C now, stop running that stupid fan.
Smart Fan: Doh... Where's that swtich again?
Smart Fan: Okay, its off.
Bios: Its 40c now.
Smart Fan: Okay, this is getting annoying.
:lol:. o O (Okay... so I have too much time on my hands)