My CPU fan is switching off. I had an initial problem with my Asus A8N
Nvidia Nforce4 SLi chip fan not coming on when my PC booted up, I
managed to sort that out by taking the Motherboard out and taking the
fan off and putting a little WD40 on to it. After putting the
Motherboard back into the case and reconnecting everything I kept the
side off the case and noticed all fans were spinning but after about
15 secs the CPU fan turns off. One thing I have noticed though and not
sure if it's connected, if I only connect the 24 pin ATX power
connector and keep the 4 pin 12v ATX connector off the fan spins all
the time but I cannot switch the PC off without pulling the mains plug
from the socket, with the 4 pin 12v ATX connected the fan on top of
the CPU switches off after the 15 secs and I can switch the PC off as
normal. Is the problem related to the PSU then? BTW, the CPU heatsink/
fan were not removed when I took the Motherboard out for the SLi chip
fan problem above. Any help appreciated.

TIA

On 2007-11-12, sabmorgan@aol.com <sabmorgan@aol.com> wrote:
What makes you think that you have a problem? It's quite possible that
the CPU fan won't run unless or until the CPU reaches its normal operating
temperature - cold things need no cooling )

--
-- ^^^^^^^^^^
-- Whiskers
-- ~~~~~~~~~~

added these comments in the current discussion du jour ...

CPU with no fan running will begin to overheat and likely your
BIOS will shut down the system in about 30 seconds. Whether that
long running hot is enough to damage an expensive CPU cannot be
predicted with accuracy. Assuming you have a newer, hot clock
rate CPU such as my AMD Athlon 2..6 GHz, then besides the fan,
there is a rather think aluminum finned heat sink. And, there's
this guck called CPU grease or heatsink grease or some such
between the chip itself and the heatsink and more of it between
the heatsink and the fan. This stuff is crucial! Its two main
purposes are to bond the 2 parts together so heat flows correctly
between them and ensures they don't get permanently stuck. When I
watched my nephew do mine a year or so back, he bought a small
tube of the white grease, squeezed some onto the parts, and
spread it around evenly with a small piece of light cardboard.

Now, if your motherboard has a utility like my Asus, there will
be a utility hidden in its folder and in your Start menu that
will allow you to monitor all the fans, temperatures, and
voltages real-time much like what you would see in BIOS set-up,
but with a GUI within Windows. It is VERY handy when trying to
determin if you do or don't have a problem that will kill
something.

Good luck!

--
HP, aka Jerry

Whiskers added these comments in the current discussion du jour
....

My AMD Athlon 2.6GHz CPU fan runs all the time, about 5,200 rpm.
When starting cold, it is slow for about a minute, starting at
around 2,600 rpm and accelerating. Some are variable speed, mine is
a constant speed fan. But, if the CPU manufacturer has a fan on the
CPU at all, and likely they will these days, then it is a damn good
idea to determine without any doubt if the fan should be running
all the time or whether it is normal to cycle. If you guess wrong,
at the least, the CPU may/will overheat and the BIOS will shut the
system down. At worst, the chip may fry itself. Too much money
involved to fool around, IMO.

--
HP, aka Jerry

HEMI-Powered "contributed" in 24hoursupport.helpdesk:

You are a waste of flesh. You have no rhythm. You are ridiculous and
obnoxious. You are the moral equivalent of a leech. You are a living
emptiness, a meaningless void. You are sour and senile. You are a disease,
you puerile one-handed slack-jawed drooling meatslapper.

--

You're so stupid, you thought meow mix was a record for cats.

<sabmorgan@aol.com> wrote in message
news:1194892672.115138.171030@50g2000hsm.googlegro ups.com...

Not unusual for modern motherboards to turn the CPU fan down to a slow speed
(or even stop) when the CPU is at a low temperature.
It's all aimed at reducing the wind tunnel fan noise created by fans running
at full tilt.

Most of these motherboards will start up with the CPU fan running at high
speed until the boot process has progressed enough for the motherboard to
read the temperature sensor inside the CPU.

Read up the specs for your motherboard in the supplied manual and you will
see it supports 'ASUS Q-Fan2' which is the name ASUS gives to it's method of
controling the CPU fan speed in this fashion.

You do need a compatible fan for this to work, but most of the retail Heat
Sink/CPU Fan unit's I've seen lately have been compatible with Q-Fan.

Best
Paul.

Starts at 2,600 and goes to 5,200 and it's a CONSTANT speed fan? You need a
new fan. Mine starts at full speed for a second or two on a cold start and
then varies it's speed as the processor's load increases and decreases.

Larry

"HEMI-Powered" <none@none.en> wrote in message
news:Xns99E69A239D7B6ReplyScoreID@140.99.99.130...
: Whiskers added these comments in the current discussion du jour
: ...
:
: > What makes you think that you have a problem? It's quite
: > possible that the CPU fan won't run unless or until the CPU
: > reaches its normal operating temperature - cold things need no
: > cooling )
:
: My AMD Athlon 2.6GHz CPU fan runs all the time, about 5,200 rpm.
: When starting cold, it is slow for about a minute, starting at
: around 2,600 rpm and accelerating. Some are variable speed, mine is
: a constant speed fan. But, if the CPU manufacturer has a fan on the



--
Posted via a free Usenet account from http://www.teranews.com

John Holmes added these comments in the current discussion du
jour ...

thanks, you seem like a nice guy, too

--
HP, aka Jerry

"Whiskers" <catwheezel@operamail.com> wrote in message
news:20071112194255.3F2A.e.NOFFLE@ID-107770.user.individual.net...
Er the fact that the fan is always on, period. That's what makes me think I
have a problem. Anyway, I seem to have fixed it (fingers crossed), I took
the heatsink/fan off the CPU and spread the thermal paste around a little
that seems to have stopped the PC switching off and for some unknown reason
the fans going all the time, maybe just a glitch, but for now I'm happy.

HEMI-Powered "contributed" in 24hoursupport.helpdesk:

;-)

--
<snip>

Larry added these comments in the current discussion du jour ...

you should be wary of jumping to incorrect conclusions based on
unfounded assumptions. this is the way the fan is supposed to
work. just because your fan does one thing does not mean mine
cannot do something else, nor anyone else's do a 3rd, 4th, Nth
thing different than yours.



--
HP, aka Jerry