Interpreting CPUID

masplin · 30 Dec 2011

Every few weeks my Dell Vostro 350 starts making a horrible noise which I suspect is the fan. if I reboot it goes away for a while. I downloaded CPUID to check the fans/tempratures and attached is what I see. Does any of this look unusual? What is Fan PWM that is always 100%. When I rebooted and ran it again it look pretty much the same i.e. no obviously high temp and fan speeds similar.

Is there anything else I could run to test my fan? Could it be something physical that builds up over a few weeks?

Thanks Mike

Manigue · 30 Dec 2011

masplin said:

What is Fan PWM that is always 100%. When I rebooted and ran it again it look pretty much the same i.e. no obviously high temp and fan speeds similar.
Thanks Mike

Hi Mike;

My CPUID report does not show the PWM value. But a search in Google took me to WikiPedia and I found this:

Fan types

Common cooling fans have at least two pins on the connector. These two pins connect to the fan motor, usually a brushless DC type. Extra pins may be present, with either or both of the following features:

A tachometer that measures the actual speed of the fan as a pulse train, frequency being proportional to speed.
Control of fan speed using PWM (Pulse-width modulation.)

Two-pin fans operate either as an on/off fan, or can be controlled by varying the voltage. Fans will have either two, three, or four pins on the connector.

Sorry I can't provide more info on your subject.

Anak · 30 Dec 2011

Take a look at this:
SpeedFan - Access temperature sensor in your computer
You can throttle your fans with this.

And your question about PWM:
SpeedFan article: What is PWM and how is it used to control fan speeds?

masplin · 30 Dec 2011

Normally my fan is almost silent despite the readings I posted and PWM of 100% so most of the time it isn't an issue with the fans being overactive. It just every few weeks it starts to make a racket. The question is does PWM of 100% just mean 100% duty cycle as per your link and is this normal? Presuming it is the CPUID report didn't look much differnet when it was making a racket this morning. Is there anyway of forcing the fan to maximum speed to see if I can reprodcue the noise?

Sardonicus · 30 Dec 2011

You may have a fan that is needs replacing. 100% is normal on Dell systems and set that way for
stability. Since the fan speed increases based upon load, to replicate, you probably need to do something
that is CPU intensive.

masplin · 30 Dec 2011

Last couple of times its been overnight when you wouldn't expect it to be doing much but virus scans. OK well thanks for clarifying that what I'm seeing is normal for CPUID.

masplin · 30 Dec 2011

Was just tapping around to see any easy way to stress my pc and came across OCCT. Being Russian is this actually safe as Kapersky thinks it's a trojan? Is this a good way to push my CPU and fans and see if I can produce the noise?

Golden · 30 Dec 2011

Hi,

OCCT is legitmate (make sure the download site is good!) - see this guide which only details the GPU stress tests:

NVIDIA/AMD Video Card - Test with OCCT

OCCT CPU stressing uses the LINPACK libraries, but so does IntelBurnTest, which is quicker.

You could try IntelBurnTest which will really stress the CPU (and fans). Run 5 standard tests.

You must:
1. Know exactly what your CPU maximum temperature (TCase) is - find out here:
Intel® Core)

2. Monitor your temperatures very closely - use HWINFO64 for that.
HWiNFO64 Download

IMPORTANT : If the CPU core temperatures shown in HWINFO64 start approaching the TCase tempearture of your CPU, you MUST immediately stop the test to avoid overheating and damaging your CPU. I cannot stress this enough.

Regards,
Golden

Dwarf · 30 Dec 2011

Have you checked the fans/heatsinks to see if they need cleaning of dust?

masplin · 30 Dec 2011

Ok that did it. Temp climed to 72C very quickly (<1min) so stopped the test. I now have a horrible noise coming from the pc which sounds like the fan. However CPUID shows the fan RPM has dropped back to normal. I'm guessing it should get so hot so quickly!! I'll open it up and give it a good clean out as suggested, but if it does this again can I assume I have a problem with either fan or heatsink?