Re: Driver responsible for CPU fan control?

Again, contact the manufacturer while still under warranty. Laptop computers come with manufacturer supplied power/fan monitoring software/hardware. The manufacturer best knows how to troubleshoot these supplied services and devices.

When you know for certain that there are no manufacturer supplied utilities or hardware that may be causing the problem you can then start inquiring of Vista.

Until then you are just chasing your tail.


Richard Urban
Microsoft MVP
Windows Desktop Experience

"Markus Eßmayr" <essmayr/at/> wrote in message news:#aSCz$psJHA.4068@xxxxxxxxxxxxxxxxxxxxxxx
Thanks to all for your comments, but I'm still sure, that this is not a hardware failure.

I spent some time to do some tests again.
Here are the results.

1. When turning on the laptop in a cold state, the CPU fan starts for 1 or 2 seconds and then stops again.
2. Then the system (Windows Vista) boots (still no CPU fan, even the CPU gets much warmer).
3. Until I reboot the machine, the CPU fan does not run!
3. As soon as I reboot the machine (while the BIOS-POST runs), the CPU fan starts. It does not matter, if I reboot the machine immediately when the logon screen is displayed, or after some work (which makes the CPU quite hot of course).
4. Then the system boots again keeping the fan speed.

So my problem is definitively located somewhere in Vista.
There must be a driver or something else, that prevents the fan to start while Vista runs.
If I turn on the laptop and enter the BIOS setup, the fan starts automatically after some time, like it should also be in Windows.

So, my question again.
Which driver or component could be responsible for manipulating the CPU fan behaviour?

"Markus Eßmayr" <essmayr/at/> schrieb im Newsbeitrag news:uESVeV4qJHA.3792@xxxxxxxxxxxxxxxxxxxxxxx

since a few weeks I have the following problem with my Notebook.
(Toshiba Satego X200)

If I start it the first time (with cold CPU), the fans initially don't run.
But even after Windows Vista started, and the CPU is "warm enough", the fans don't start.
But it I reboot the Notebook, as soon as the POST runs, also the fans start.
Then, also if Windows is up, the fans keep on running.

Is there some kind of driver in Windows, that may have influence on CPU fan control?
It's very annoying to boot twice each day!