T410s fan running constantly 4000 RPM

[lobo1978]

Hi, I've upgraded my T60 to T410s recently. I've bought two identical units: 2904-FXG (i5 520M, Samsung 126GB, Intel HD, all updates installed, latest bios etc.), the only difference is that one of the have 4 GB of RAM (the other 2 GB).
And now the interesting part. One of the units is running completely fan less, the other almost full fan speed lock (4000 RPM). I've synced settings in power manager on both t410s and the situation stays the same. Switched the ssd on machines... It turns out that ssd from quiet unit hasn't changed behavior of loud one.

Systems are completely the same - I've monitored cpu load, multiplier state, throttling etc.

It's not the system/win7 issue. It's BIOS - embedded controller (units have the same bios rev.). Maybe some fault during assembly?

Any ideas how to solve this problem.

[lobo1978]

Anyone? or all of you just installed tpfan and forgot about fan?

BUT

Is it ok that in machine worth almost 2000 EUR you are forced to use freeware (excellent one btw!) to solve faulty Lenovo ACPI controller?

[Harryc]

Reset the BIOS to defaults and reboot

[lobo1978]

Little update on issue: not resolved - I've already tried with downgrading bios.
Running TPFancontrol service in the background.
Silence.
Still waiting for lenovo solution though

[Larswa]

This does indeed seem strange. What has Lenovo Support had to say about this?

For reference - My T410S is almost always running at around 4000 RPM's, but it is a switchable model and I mostly run it on the discrete grachphics card, where it gets a bit hot.

When running it on discrete graphichs it usually runs a little slower. Around 3500 RPM, but it NEVER stops completely.

[Matthew_Greening]

This is really bizarre but similar fan noise issue have been reported for other new ThinkPad models. Some are blesses with a silent fan while other have the same model and struggle to reduce the noise.

Have you been able to track down what causes the different fan speed behaviour? You are in an unique position with the two identical notebooks. Well, not unique as Lenovo could have done the homework themselves.

[jayton4]

Since the memory is the only thing that is different on the two, I would start by ruling that out. On the one that has 4GB ram, is it in 2 x 2GB configuration or is it 1 x 4GB? Just for troubleshooting purposes, try putting them both at 2GB ram to see if they behave any differently.

Try monitoring temperatures with an app like Speedfan. Maybe the thermal paste on the heat sink of the loud one needs to be reapplied.

[sir_synthsalot]

My T410s also does it. 4000 rpm at all times even when idling. I have integrated graphics. If not for TPFancontrol I don't know if I could ignore it. I don't think the RAM would make a difference, it doesn't make sense, and from experience I had 1x2GB orginially and now I have 2x4GB and there is no difference.

What about temperatures between the units? Does one of the units run cooler or is the fan just running at higher speed?

I think this chasis/cooler may not be well-designed for a 35W CPU. It's basically identical to the T400s with updated hardware. The T400s originally came with low voltage 25W SP9000 series processors. I think they just stuck a hotter CPU in it and as a result you get a louder fan.

I'm tempted to re-apply the thermal paste on mine although it is a lot of work.

[racc]

I changed the thermal compound of my T410s (integrated graphics) to Arctic Silver 5, which should be quite good thermal paste.

I would not especially recommend this. IMHO T410s is much more difficult to service than e.g. T60 or T43p. At least one should have good screw drivers (!), hardware maintenance manual and enough time. T410s needs to be disassembled almost compeletely before one being be able to change the thermal paste. But if you like this kind of tinkering, go ahead!

I did not notice any temperature or fan noise reduction, though my measurements were very limited, only idle usage.

T410s embedded fan controller seems to have strong hysteresis, especially when using AC power. I have not measured the exact behavior, but it looks like if the temperature rises slightly over 40C, the embedded controller kicks fan to 4000rpm (not really badly noisy, but irritating especially in a silent enviroment when trying to focus on something else) and does not lower speed/noise until the temperature sensor (the only one?!) reports temps in the range of 34C (if my memory serves right). Reaching that temp is possible very rarely. This is frustrating, because even the slower and nearly silent 3400rpm (level 2) speed setting is able to keep near idle CPU temp under 45C quite well.

Example: T410s i5-M520, SSD, approximately 6-10% CPU load, fixed 3400rpm, 49C.

Embedded fan controller seems to behave very differently when on battery power, though even BIOS settings are set same for both power sources. On battery, the EC kicks the fan to noisy speeds in significantly higher CPU temps. Therefore I thought it was safe to write a small python script to set fan speed to low-noise (3400rpm) when CPU temp reaches 41. In 45 degrees the fan control is returned to the EC automation. I have no problem with computer making noise if it has some real CPU load. This reduces disturbing fan noise pretty nicely, and I hope it doesn't reduce the lifespan of electronic components too badly.

[gcafrk]

I installed LION 10.7.2 on my T410-2522-RT8. Its fan speed is around 3600RPM. I updated BIOS to latest version of 1.40.
CPU temp is from 38'c to 50'c. It sounds OK.