Howard;
I believe most cpu fans have traditionally run constantly, but  some
motherboards
can stop the fan when the system enters suspend mode.
The cpu fan has to be plugged into a "controlled" cpu fan header on the mobo
for this
feature to work.
On the ones I have seen, there are settings in bios to enable/disable this
feature.
I was surprised the first time I saw this, but the heatsink wasn't warm to
the touch.
 As soon as I moved the mouse the cpu fan kicked back on.
I have also seen variable rpm fans that have a thermistor or "thermostat"
that varies the fan speed depending on the temp. of the cpu.
 The lastest breed of cpus from Intel and AMD run very hot and require a
heatsink/fan to avoid "frying" the cpu within a few seconds, but in suspend
mode very little heat seems to be generated.

     |
  --|---------------------------
     | ><>  Larry  Fisk   <><
     |      Fisk Computers
     |      Fruitvale, Idaho

----- Original Message -----
From: "Howard Marschner" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, May 25, 2001 6:35 AM
Subject: [PCBUILD] CPU fan


>    Dear good helpful folk
> Generally speaking, Do CPU fans run constantly to keep them cool or
> intermittently like a thermostat to keep them at a constant temperature?
> thanks
> Howard Marschner

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