How to stop fan from revving?

My colleague is using a Fujitsu Esprimo E900 (VFY:E0900PXG11NL) desktop PC that revs its fan every couple of minutes when a CPU core hits 70 degrees Celsius according to SpeedFan 4.51. Enabling "Automatic fan control" in SpeedFan doesn't help much (Is it still learning? Does not being able to show fan speeds affect it?).

The CPU is almost idle and there's no apparent dust in the case and another colleague says it's always revved. Is there a BIOS setting to control the fan speed?

Room temp is 25 C and desktop is clear. HDD temp is 40 C and average idle core temp is 60 C.

It appears that the fan can be controlled:

Special Features

Silent Fan - Independent temperature related processor fan and system fan supervision and control

System Guard - View and adjust Silent Fan features

Unfortunately, Enhanced mode makes the front fan rattle (otherwise it would be the answer), Silent mode doesn't help, and Disabled makes it sound like a vacuum cleaner. I could ask the hardware guy about the thermal paste but all stock paste i've used lasted much longer than this and it seems all fans are entirely off until needed.

My colleague is fine with the revving on Auto, so i can't test SpeedFan again while BIOS fan control is disabled.

Cees Timmerman

Posted 2015-09-23T08:49:07.417

Reputation: 1 240

How old is this PC? Is this a new problem? What's the ambient air temperature? Are all intake and exhaust vents clear and unobstructed? Is there at least 12" of open space in front of every vent? Is the PC in a cabinet, bookcase or under a table? – sawdust – 2015-09-23T09:21:05.400

70 degrees Celcius is quite hot for an idle CPU, in fact, it's quite near the TCase of 72.6 for the i5-2400. Assuming it's a pre-assembled machine, given the brand, you can't replace the thermal paste or cooler?

– CodeCaster – 2015-09-23T11:04:16.543

Do what @CodeCaster has said above here, replace thermal paste and cooler to something that will fit and cool more efficiently. That should fix the problem long term and give extended life to the hardware itself by getting the temps down. – Christian Isaksson – 2015-09-23T13:00:48.740

It's from late 2011.

– Cees Timmerman – 2015-09-23T13:03:21.730

Sounds like an AMD processor? – Moab – 2015-09-23T23:03:57.900

@Moab, CPUs don't make noise, and it's an i5-2400@3.1GHz. – Cees Timmerman – 2015-09-24T07:41:21.063

I know that, AMD's run hotter than their Intel counterparts. – Moab – 2015-09-24T11:48:41.370

possible duplicate of Utility to manipulate speed of fan in Windows 7

– Cees Timmerman – 2015-09-24T11:52:06.727

Now the answers are in the question. – Cees Timmerman – 2015-09-24T16:05:48.490

@CodeCaster, Tcase is much lower than my Tcpu, else the heatsink would be useless. – Cees Timmerman – 2015-10-05T10:54:33.643

Answers

In the "Advanced" section of the BIOS, set "Fan Control" to "Enhanced". This has the added benefit of maximizing CPU performance.

My colleague nor I notice the slight rattle that results in our case, so there's no need to try SpeedFan while BIOS fan control is Disabled.

Cees Timmerman

Posted 2015-09-23T08:49:07.417

Reputation: 1 240

Enabling "Automatic fan control" in SpeedFan doesn't help much

Is it still learning? Does not being able to show fan speeds affect it?.

If your motherboard is supported by SpeedFan then it should show the fan speed.

Normally SpeedFan is very good at auto detecting the temperature and fan speed sensors.

Unfortunately your motherboard does not seem to be in the list of motherboards that can change fan speed.

Image source Motherboards from FUJITSU/SIEMENS that can change fan speeds

Disclaimer

I am not affiliated with SpeedFan in any way, I am just an end user of the software.

DavidPostill

Posted 2015-09-23T08:49:07.417

Reputation: 118 938

"This is a subset of the hardware that SpeedFan can properly work with." – Cees Timmerman – 2015-09-23T17:32:13.317

@CeesTimmerman Also from that page "Don't blame me if the revision of the motherboard you've purchased can't change fan speeds the way you hoped". Perhaps you should send an email to the developer? alfredo@almico.com – DavidPostill – 2015-09-23T17:37:03.440

I would if i could test SpeedFan while BIOS fan control is disabled. – Cees Timmerman – 2015-09-24T07:39:53.613

The mobo can change fan speeds just fine on its own (except one fan rattles at slow speed). – Cees Timmerman – 2015-09-24T11:58:42.203

@CeesTimmerman I still think you should send an email to the developer alfredo@almico.com – DavidPostill – 2015-09-24T12:00:21.233

I'm awaiting his reply. – Cees Timmerman – 2015-09-24T12:15:42.540