DeLyle, the appropriate minimum fan setting for the warnings will depend on 
the fan and what its normal speed range is.  I'd say leave the CPU as it is, 
if it is running and you are not getting any warnings.  I think that main 
point of these warning is to let you know when the fans have completely 
stopped running.

For the chassis fan, it is possible that a large case fan, such as a 120mm 
fan could run slower than 500 rpm and still be in its normal range, but I 
also wonder if the fan you installed has a three wire connection.  If it is 
just a two wire connection, you won't get any fan monitoring; so, it will 
show up as failed.  It's also possible that the fan is plugged into a 
motherboard header which is different than the one you are setting the 
warning thresholds for.

Typically, motherboards with the capacity for adjusting warning thresholds 
will also have a section in the BIOS where you can see the current fan 
speeds and other things such as the CPU temperature and maybe voltage 
readings.  Do you see something like this?  What are the fan rpm readings in 
this monitoring section, if such a thing is available.

The simplest solution, if you can readily see that all your fans are 
working, is just to disable the warning for the fan that keeps saying it 
isn't up to speed.  Of course, I'd probably want to know why I was getting 
this message before resorting to that solution.

John Sproule

-------- Original Message Below --------

Date:    Sun, 17 Oct 2010 12:17:50 -0700
From:    DeLyle Dvorak <[log in to unmask]>
Subject: Computer Fan Speed Warnings

I'm running a desktop computer with ASUS motherboard, using XP Pro, SP3 
(built
for me 5 years ago). Recently it began exhibiting fan speed warnings at 
start
up:
CPU Fan speed to low and CHA1 Fan Speed too low or not working.

After trying some options previously posted on this site, I replaced both 
fans.
I'm still getting the error message about the CHA1 fan and at some bootups, 
the
same error with the CPU fan, but not every time. I went into the settings, 
but
am not sure what the speeds for each of these fans should be set at. The 
options
on the CHA1 fan are speeds of 500, 800, 1200 and the CPU fan 800, 1200, 
1600.
The CPU fan seems to be okay when set at a warning speed of 800, but the 
CHA1
fan produces the warning, no matter at what speed is set (it also shows the
option of disabling the warning). The fans appear to be working fine, so am 
I
having a motherboard problem instead of a fan problem?
I'd appreciate any help or advice.
Thanks.
DeLyle Dvorak

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