Hi!
There is *no* need for the exhaust fan to run at 1000 RPM.
There's the problem that you run into as a motherboard maker. Do you run the
fans as slowly as you can, or do you try to make sure that pretty much any
fan will actually run and move enough air to be helpful? You can't possibly
cover all the fans and case designs there are, so some error on the side of
caution happens.
But if it's possible to slow things down with speedfan, I'd rather do
that instead.
It *might* be. The manual for my Asus M2A-VM board says that only the CPU
fan may be adjusted through Q-Fan control. Even though the ITE LPCIO would
happily control about six thousand fans (exaggeration, but you get my
point), Asus only implemented control of *one*. It baffles me.
I'm baffled by the zillions of controls and the lack of documentation.
It becomes less baffling when you think about how many different hardware
monitor ICs there are. And there are a lot. Maxim-Dallas, SMSC, ITE, Analog
Devices, Myson Century, National Semiconductor and others all make them.
Each one works differently. I dare say that the author of SpeedFan had to
work from datasheets and end user reports for the ones he doesn't actually
have.
The first place to go--to see if you've even got a chance--is into the
Configuration dialog. Go to the Advanced tab, and find your hardware
monitor/fan controller in the list. Click on it. You get a list of options,
and it will vary depending upon what your motherboard actually supports.
WARNING: Seriously, read and heed this warning before you continue. Some
motherboard makers get really, uhm, creative with their implementation of
the fan control and temperature monitoring circuitry. This includes
programming them in ways that only make sense to the system BIOS. You may
find that you cannot effect any sort of change on your motherboard's fan
behavior. Or you may find that your motherboard behaves unexpectedly. Your
computer could crash while adjusting settings. Close all your programs, save
your data, and maybe even consider making a backup.
Personal experience says that if you see a sudden power-off when tinkering
in SpeedFan, it's because you've caused a thermal sensor to trip. This could
be the result of enabling a sensor that provides no meaningful reading, and
is "pegged" at the extreme ends of its range. This can make the board's BIOS
think it is seriously overheated.
You're looking for something along the lines of "PWM" or "Fan Control".
Whichever one you have will probably be set to something like "Auto",
"Thermal Cruise", "Controlled by Temperature x", "Manual" or "Disabled". Set
one to "manual" and check the "remember it" box. If your setting was
effective, you may hear a fan go full throttle.
Time to take the side off your case and see what effect the speed
spinbuttons have. Watch your fans while you run each one up and down. See if
you can slow, stop or speed them up. DO NOT leave fans stopped for any
length of time, especially CPU fans!
If you found that you can control your fans, you may be in luck. Now you
need to set up a baseline speed for them to run at. Just setting the speed
in the main SpeedFan window won't work--it won't remember them the next time
you reboot. Instead, you have to define a "configuration". This is done by
using the first few tabs in the Configure window. You'll probably be most
interested in the "Temperatures" and "Speeds" window. In Temperatures, you
can expand each temperature sensor and tell SpeedFan which temperature
reading will control which fan(s). You set a desired temperature, and a
warning temperature.
When you have that done, go over to the Speeds tab. Here you can set the
minimum (and maximum) speeds that a fan can achieve.
Hopefully that helps a bit.
William
