bizarre laptop fan behaviour

[dbaker]

I just got my first Linux laptop a few days ago (details in my signature). It's great except for one thing which is starting to drive me crazy: the fan is constantly spinning up and down.

When the computer is idle for a while (literally completely idle - doing ABSOLUTELY NOTHING) the fan won't spin up, but the moment I do anything - touch the trackpad, start typing, move the cursor - it'll spin up, and then spin back down again after 2 or 3 seconds. This happens constantly and as you can probably imagine, it's incredibly annoying, especially since the fan is quite loud. Every now and then, it'll actually spin up and down again several times in the space of a couple of seconds.
I don't know why this is happening but it seems like it's maybe just too sensitive to tiny temperature changes associated with slightly increased CPU activity?

The laptop has 2 large air intakes on the bottom of the case, which is elevated about 5 millimetres with little rubber feet, and a gigantic outlet on the side of the case, which I can feel hot air blowing out of when the fan spins up. This is much better ventilation than my old Macbook, which was always overheating (probably largely due to dust, as it got worse and worse over the years). The new laptop certainly feels MUCH cooler to touch than the Macbook ever did, although I noticed today that it's getting quite hot on the actual trackpad, which is a tad unpleasant (especially in summer; in winter it would probably be lovely. Computers as hand-warming devices!)

What do you guys think about this issue? Might it be possible to configure the fan somehow (in BIOS settings, or elsewhere?) I really don't know anything about this kind of thing :S

[dbaker]

oh no D: do you think it's something that's more of a problem than just a minor nuisance/could be harmful in the long term? I waited so long for this computer and I'd be terrified of entrusting it anyone for repair now, not to mention having to pay to ship it back to the supplier. my protectiveness of it is the main reason I don't want to do that though

[oshunluvr]

Teunis didn't say ship it to the supplier, he said contact the supplier. With a new laptop (or any other new product for that matter) that would be the first thing to do. They might be able to tell you how to adjust the fan response timing. Sounds to me like it over-reacts to an initial increase in activity and then settles down once the temperature settles. Could be that it's not supposed to be acting that way and needs replacement. Better to know that now rather than after warranty expires. But you'll never know for sure if you don't contact the supplier.

[dbaker]

true. I was talking about shipping to the supplier because, if something turned out to be wrong, I'd have to do that.

[GreyGeek]

According to this site the maximum operating temperature of the i5-3230M CPU is 105F.

Install the Hardware Temperature plasmoid onto your tool bar and select either the lm-sensor (which uses the fancontrol package) or the acpi/thermal setting for your primary core. You may have to install the lm-sensor package. If your temp goes beyand 95F you may get stuttering in your performance, usually indicated by the screen freezing momentarily until the temp drops below about 95F. (That what happened when my Acer laptop began acting up. I solved the problem by blowing dust out of my CPU cooling system, which dropped the idling temp from 120F to about 100F.)

[dbaker]

that's 105 Celsius, not Farenheit

I am already monitoring CPU temps, and have lm-sensor installed. acpi too.
I have it outputting the temps to conky so I can keep an eye on them all the time. They're usually between 40-50 C regardless of what I'm doing - presumably a fairly normal temperature range?

[dbaker]

in case anyone thinks there's actually an overheating problem that's causing the fan to behave strangely:
I have conky on my desktop showing temps and CPU activity, and am constantly watching it to see what happens. Sometimes I can see a correlation between increased CPU usage and the fan spinning up, though not always.

Observing the fan behavior and temperature over the past 10 minutes or so, I'm seeing what appears to be a roughly 50C threshold for the fan to spin up: watching the temps of the 2 processor cores, with the fan off they tend to reach 48-49 C before the fan spins up, after which they go down to 43-45 C then creep up again before hitting the threshold and the cycle repeats.
A few minutes ago, the temps stayed around 49C for long enough without the fan spinning up for me to notice that they didn't climb any higher than that, so I'm guessing if the fan wasn't constantly lowering them they'd stay around that temp most of the time when idling.

[GreyGeek]

that's 105 Celsius, not Farenheit

Opps! My bad typo...

I am already monitoring CPU temps, and have lm-sensor installed. acpi too.
I have it outputting the temps to conky so I can keep an eye on them all the time. They're usually between 40-50 C regardless of what I'm doing - presumably a fairly normal temperature range?

That temp range appears to be normal. My i7-3010M CPU idles around 37-40C and running Minecraft, for example, both the server and the client, it stays around 50-60C, oscillating back and forth between that range rather quickly depending on how many chunks are loading. Conky's nice to show temperature but I keep the Hardware temperature plasmoid on my toolbar so I can see it when apps are running without having to click the desktop icon to minimize all app and expose the Conky display.

One thing I have noticed is that when I replaced 12.04 with 14.04 the 3.13.x kernelsin 14.04 seem to run a lot cooler than the 12.04 kernels, and are somewhat faster.

Also, since you have lm-sensors installed you probably also have fancontrol and its config tool, pwmconfig installed as well. Read the man pages for those, especially pwmconfig, which allows you to set the start and stop temperature ranges for the fans. Assuming, that is, your fan can be controlled by pulse-width-modulation.

[dbaker]

I have been looking at fancontrol, but am absolutely terrified by the idea of switching fans off for even 5 seconds. I configured lm-sensors, including adding the module to the kernel. Also terrifying. I'm scared to restart now. Someone reassure me? lol

that's interesting about 14.04. I didn't even know it was out until after I ordered my laptop! definitely not going to upgrade until it's stable though.

[GreyGeek]

I've been running the 14.04 Alpha since sometime in January, right after it was announced, and it has been very stable for me. It should be going beta soon because the release is in 4 weeks.

[dbaker]

awesome. I'm going to install it on one of my VMs (or make a new one) and see what happens.
Any suggestions, once I have the courage to do configure my fans, about max/min temps and speeds etc? I could take a guess at it but I want to be sure whatever I do is going to be the best thing for the health of my hardware in the long term :\

[GreyGeek]

Run the command
senosrs
in a Konsole and see what measurements lm-sensors is giving you.

Here is what is shown when I run it:

$ [FONT=courier new][B]sensors[/B][/FONT]
acpitz-virtual-0
Adapter: Virtual device
temp1:        +43.0°C  (crit = +102.0°C)

nouveau-pci-0100
Adapter: PCI adapter
temp1:            N/A  (high = +95.0°C, hyst =  +3.0°C)
                       (crit = +105.0°C, hyst =  +5.0°C)
                       (emerg = +135.0°C, hyst =  +5.0°C)

coretemp-isa-0000
Adapter: ISA adapter
Physical id 0:  +42.0°C  (high = +87.0°C, crit = +105.0°C)
Core 0:         +42.0°C  (high = +87.0°C, crit = +105.0°C)
Core 1:         +39.0°C  (high = +87.0°C, crit = +105.0°C)
Core 2:         +36.0°C  (high = +87.0°C, crit = +105.0°C)
Core 3:         +36.0°C  (high = +87.0°C, crit = +105.0°C)

pkg-temp-0-virtual-0
Adapter: Virtual device
temp1:        +42.0°C

As you can see, for my hardware, sensors does not show fan speed.

[dbaker]

it doesn't for me either is that going to be a problem? presumably there are other utilities for getting fan speed?

acpitz-virtual-0
Adapter: Virtual device
temp1:        +27.8°C  (crit = +106.0°C)
temp2:        +29.8°C  (crit = +106.0°C)

coretemp-isa-0000
Adapter: ISA adapter
Physical id 0:  +49.0°C  (high = +87.0°C, crit = +105.0°C)
Core 0:         +47.0°C  (high = +87.0°C, crit = +105.0°C)
Core 1:         +49.0°C  (high = +87.0°C, crit = +105.0°C)

pkg-temp-0-virtual-0
Adapter: Virtual device
temp1:        +49.0°C

[GreyGeek]

More than likely if sensors does not show the fan speed then I suspect using pwmconfig would have no effect because lm-sensors is not detecting fan speed. It can not change what it does not detect. My kernel logs show that during boot up the fan control is set to "automatic". I do not know what that implies, but on my system the fan seems to be generally off unless either the GPU or the CPU temp begins to rise, and then I can feel a gentle breeze from the fan exhaust port. It becomes forceful if the temps exceed 60C or so, but the fan is never noisy. I suspect that it is probably under BIOS control.

As far as running pwmconfig, I wouldn't. If lm-sensors was able to find your fan it would have set up a default pwmconfig conf file which would be used to set virtual params in /proc and which you would be able to adjust using pwmconfig. I'm just guessing, though. Like the old saying says, "If it isn't broken then don't fix it". Your fan is working, and somewhat automatically.

[dbaker]

hmm, do you think it would be worth taking a look at the BIOS settings? It has a thing called 'insyde' for controlling them. I don't know anything about it yet, but I believe it's covered in the user manual.
The fan is certainly doing its job, and I don't want the laptop to overheat, but it would be nice to make it less over-reactive :S I worry that it might wear out quicker with this constant spinning up and down.

I was taking a look at the bottom of the laptop where the air vents are last night. There's a perfectly circular one towards the left and back of the case through which I can see the fan (if it spins up and I put my hand against that vent, I can feel cold air whooshing). That also corresponds to the outlet at the side that blows out hot air. But there's another bigger, square vent on the bottom of the case (also on the left, but towards the front) which doesn't seem to have a fan behind it and feels neither hot or cold. I'm curious what that's for. I can just see a copper-colored thing through it - heatsink?
Bear in mind I've always had macs which have cleverly hidden and almost non-existent ventilation, so these things are new and fascinating to me :P