CPU fan constantly set to 800rpm

ciaal

Distinguished
Aug 26, 2008
3
0
18,510
I did quite a few things that would be common to fix such a problem like disabling settings in BIOS such as Cool'n'quiet and SMART... I also even used a pin-to-molex adapter to plug the fan directly into the power supply.

This is a fairly expensive heatsink with said speeds of over 3000rpm so this 800rpm is causing my overclocked AMD 5000+ Dual Core running @ 3.0ghz to reach high temps.

fanissue1.jpg


Hope this image helps in explanation of the problem and thank you for your time.
 

r-sky

Distinguished
May 8, 2007
432
0
18,810
If you plugged the fan into a molex to use 12v then you will not have any speed reporting on the fan...

It just runs off 12v. It may have a thermal resistor to increase the fan speed as the heat goes up. (just like the original K8 fans...)
 

ciaal

Distinguished
Aug 26, 2008
3
0
18,510
I did a lot of tests before I plugged it into a molex... And I also did fan test speeds on it during stress tests... Running heavy load @ 65c with fan still capped to 800rpm.

I was hoping for a response that didn't contradict with what I've already said but thanks for the time.
 

the associate

Distinguished
Jun 3, 2008
338
0
18,780
your seriously using that hsf on an overclocked am2???
id vote a defective fan if anything, or wiring issues. If it isnt a problem id recommend exchanging it for another, or a bigger/better.
In any case, id say 65c is a great temp with that munchkin, is size an issue for your case?
 
Yeah, that is hardly an expensive cooler.
More like a value cooler really.
If you want to bring your temps down, get a bigger cooler.
Also, if your CPU fan is plugged directly into the PSU, you will have no RPM readings.
The RPM is read through the 3rd pin on the fan harness through the Mb.
 

ciaal

Distinguished
Aug 26, 2008
3
0
18,510
The thing is, it's not the cooler... I know people with the same one running at 40-50c whereas I'm at 65c... And guess what, it's not 800rpm... The reason I have that cooler is because the bigger coolers don't fit in the case, and yes I've tried others. It's just the 800rpm doesn't work. And I'm not sure what you're on about with it being plugged into PSU because it was doing the exact same before and after I plugged it into the power supply. So rather than suggesting "NEW COOLER" Any real ideas?
 


Look.
It is pretty simple.
Your CPU fan has a 3 pin connector.
2 of the pins provide power and ground.
The 3rd is for a RPM sensor.
PCfanconn.jpg

When you connect the CPU fan to your PSU with a MOLEX adaptor, the RPM sensor is no longer pluged into your motherboard and is not providing a reading.
12-189-119-03.jpg

If you still have a 800RPM reading with the CPU fan plugged into the MOLEX adaptor, it is another fan providing the reading (or a software glitch).
The reason your cooler will not keep your CPU cool is because it is a piece of junk and you probably do not have enough airflow in your case.
 

Zorg

Splendid
May 31, 2004
6,732
0
25,790
Turn SMART back on. It is Self Monitoring Analysis and Reporting Technology for the hard drive. It has nothing to do with your fan.

I agree with outlaw. If your fan is plugged into the PSU then it is running at maximum and not reporting speeds, because it can't.

With a fan speed of 3050 - 6000 RPM that thing should sound like a tornado. Try getting a replacement 70MM fan.