Hello,
I switched out an emachine (yes), mobo that died (an ISI I think) for a new ASUS.
All went well to OS (WinXP), but my cpu fan is maintaining a 5300rpm yet temps are very low.

What I've done:
1) upgraded BIOS to latest
2) BIOS has NO OPTION for Q-Fan
3) Installed ASUS PC-Probe(good program!)- can't actually change speed settings!
4) Installed SpeedFan - can't change (speed) setting either- just readout's etc. Haven't tried mucking w/ voltages as I'm pretty much a rookie here.....
5) Installed Cool and Quiet. Adjusted Power setting in MS to "Minimal" as per AMD ManPages to no avail.

Read many posts, found one that stated this new board might be bad in this regard and to rma it; and the board deos not support Cool and Quiet and where the heck is Q-FAN in BIOS?

I did use thermal grease (but maybe not enough?). It's running very cool tho': cpu:77F; MB 71F. Vcore is 1.45v, and 3.31; 5.09 and 12.09 all look fine, yet it's not stepping thru the volts based on temp. This is a 3-wire fan plug to mobo.

Maybe a thermister is bad (is this replacable by a novice?), Can a fan go bad on high? That's all I can think of.... Thanks for any help....

What model of ASUS board did you fit? Q-Fan is the "Quiet" part of Cool&Quiet, so needs to available and enabled or the fan will run at full speed.

The mobo is
MB ASUS A8V-VM Socket 939 (AMD 64 3400+)

Do you have any case fans? They help take the load off of the CPU fan.

There is a case Fan and it's running normally (about 2000rpm's). The cpu or mb are cool. I'm worried that the fan will die since it's running so high 5300RPM's (max), and then I won't notice and the cpu will fry (unless it has this detection capability and will shut itself down).

I'm thinking that this board /cpu does not support cool and quiet. I can't find it on the AMD site anyway. Maybe I just should buy a very quiet fan for now until I buy a new computer entirely- I don't want to buy/.install another mobo

The speed that a fan runs when at full voltage is its natural design speed, so its life won't be adversely affected by running at this speed. If the fan is connected to the CPU Fan connector, the default BIOS setting should be to protect the CPU against fan failure, with audible warning and power-down. If the connection is to another connector, say Chassis Fan, this may or may not be monitored, but a board normally will not boot without a CPU Fan connection unless the CPU Fan monitoring has previously been disabled in the BIOS. (Fitting of the CPU fan to another connector could also be a cause for the fan speed not adjusting.)

You could fit a quieter CPU fan, either way the CPU will only benefit from running cool.

I checked the manual for that model board, and indeed there seems to be no mention of q-fan, although Cool&Quiet is covered. Some boards rely on the stock AMD cooler having a fan with an integral thermistor. When the Cool&Quiet software clocks the CPU down in idle periods, the cooler reduces in temperature and the fan itself slows down. Under load, the CPU is ramped up and when the cooler gets hotter, the fan speeds up. Your board may need the cooler with temperature sensing - third party manufacturers have equivalents to AMD's own design.

Thanks so much for your explanation and research herein. I've checked the mobo and the fan cable is on the correct set of pins. And yes- noting in BIOS for q-fan settings.

Are you saying I need a heatsink/fan combo that has a thermistor with it? I'm really not sure what to do next. Since everything else seems to boot up fine-- I don't want to rma. I can't find a cheap fan (only). Plenty of aftermarket fan/heatsinks! Thanks again, GR

AMD's instructions for Cool'n'Quiet should be helpful:

http://www.amd.com/us-en/Processors/Produc...5E10272,00.html

I assume you have the Processor driver installed so the OS fully understands the operating states of the CPU, if not there's a link there.

In the Installation Guide, they comment:

"If an AMD Athlon 64 Processor-In-A-Box package is not used, an appropriate 3rd party heatsink with a thermally controlled fan must be used."

If a motherboard does have thermal fanspeed adjustment like Q-Fan, that can do the same job, but as it looks looks yours doesn't, then a cooler with its own thermistor controlled fan will do it.