Fan goes nuts when screensaver kicks in!

It's Intel® Precision Cooling IF you have an Intel Or a AMD® Cool & Quiet
These Softwares Automatically adjust your Voltage and Your CPU fan speeds and your Computer Speed according to the Tempratures of the Cpu and Motherboard. The Processer Speed up the fan during Screensaver mode to release all of the heat stored up and then slows to a crawl. and until you don't activate your Processer again

I know exactly what you mean. My parents pc is like that also, it's a Gateway. Mostly when the pc is on idle or with the screen savers on with no background task the cpu fan turns itself off. The reason is that the pc detects that there's no task or program running so the cpu is not working, hence less heat and thats when it turns down the fan on slow or completely off.

You can change this setting by going to the bios and set the fan to manual and in some bios you could even set the cpu and system fan rpm manually also. But it is recommended to set this on auto.

Hi,

Which screen saver are you running? The 3D pipes and exploding balls actually put a fair stress on the system which could explain why the fan needs to come on. Try changing to the Blank screen saver and see if the problem goes away.

--Pete

that's right.
and some(non windows)3d screensavers are almost like playing games. Stressing cpu and gpu all the way.