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Re: T420s Fan noise Issue

2011-11-28, 15:12 PM

I have one problem with Bios 1.3. always wen the fan spinns up to 4k for al longer time (ore wathing HD video)  he only commes down wenn the Temp is 45°C or less. 

From 3.8 k to 3.5k goes at 55°C and that is much better then comes <45°C is only posible wen the Computer Idle for 5-10 min.


There 1.29 was better.


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Re: T420s Fan noise Issue

2011-11-28, 15:32 PM

For those of you who would like 1.29, here is the link:





T420s, i5-2520M @2.5, nVidia 4200m, 8GB DDR3, OCZ Vertex 3 Max IOPS 240GB SSD, Hitachi 320GB @7200rpm ulrabay, 8Pro x64
T61, Centrino Duo @1.8, GM965, 4GB PC2-5300 DDR2 @667MHz, OCZ Agility 120GB SSD, 7Pro x64

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Betreff: T420s Fan noise Issue

2011-11-28, 17:39 PM

Right you are @Dan0. I also received  a large discount, but the reason I haven't returned mine is that right after purchasing I left on a global work trip and my so calle '21 day return" option has expired.


It seems JameZ hasn't posted in quite a while. What is the situation? Is Lenovo testing units that T420s victims sent in? Or perhaps they just gave up.


A well informed computer expert posting on this site mentioned that the issue could possibly be a hardware design flaw, related to one of the temperature sensors being in a bad location that results in incorrectly detecting higher temps than is actually the case, thereby causing the fan to constantly run at 4000 rpm.


If this is true, and it sounds completely plausible to me, then a simple BIOS update won't help.


The question is why is has it taken 6 months (and counting) for engineering to figure out a simple problem? I'll tell you why- because they probaly realize the only way to fully fix the proble is to recall all the units and rebuilds the cooling/senosr system. Lenovo doesn't want to spend this kind of money. 


Not sure I have the energy to rant here anymore. Will wait for crumbs to be dropped by JameZ, who is clearly at the mercy of Lenovo's desire to not spend money fixing this issue. TPfan control for the forseeable future........




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Betreff: T420s Fan noise Issue

2011-11-28, 18:14 PM
There's a sensor on the CPU die... which is totally controlled by Intel. If Lenovo isn't using that sensor, then they should be able to patch the BIOS to use that and put in a different scaling algorithm.

Nothing really wrong with TPFanControl; it's customizability is useful enough to be worth it even without an actual fan issue.

W520: 2960XM, Q2000M @ 1091/1380, 32GB RAM, 500GB&750GB HDD & 500GB SSD, FHD&MB168B+
X61T: L7500, 4GB RAM, 500GB HDD, XGA screen, Ultrabase
W550s: 5600U, K620M at 1164/1281, 16GB RAM, 512GB SSD, 3K touchscreen
X200s: SL9400, 6GB RAM, 64GB SD card, WXGA+ screen
TPT1: 1839-23U

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Betreff: T420s Fan noise Issue

2011-11-28, 20:44 PM

Occupy Lenovo! :smileymad:


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  • Message 696 of 1217

Betreff: T420s Fan noise Issue

2011-11-29, 1:41 AM

Just an update on the situation with 1.30 and my particular machine.

I have a 4170-CTO that is currently running a clean installed version of Win 7 Pro x64. On battery power, the fan is fine, ramps up and down as expected.

On AC power it will ramp up and down fine for a while, but then something happens (seems to be random at this point) and the fan ramps up to 4000rpm and stays there. If the machine goes through a sleep wake cycle, it seems to reset whatever triggered it, and the fan behaves as it should again.

Lenovo is close, really close, to nailing this down. It seems as though there is a sensor that is being misread somewhere that is a null value or something, causing the fan to think it needs to go full blast. It can be observed if you install HWInfo. There are a few listings that come up and disappear in the EC sensor subsection that are pegged at 144 degrees C.

Just to cover all my bases and to provide as much info to Lenovo as possible, I am running Power Manager Software 3.64, BIOS 1.30 and Power Driver 1.64. My fan settings in the power manager are set to "Balance All Parameters".

Don't give up yet, Lenovo, let's get this fixed!


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Betreff: T420s Fan noise Issue

2011-11-29, 6:43 AM
@antsh and @Julian_Think:

That's exactly my situation also - once it gets heated and starts running at 4k, it just stays there. On my computer, this is most easily triggered by watching HD videos. Occasionally, web browsing (when there's Flash media on the site) will trigger it too.

Running 1.30, Power Manager 3.64, Windows 7 Pro x64.

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Betreff: T420s Fan noise Issue

2011-11-29, 19:36 PM
I used to have all the problems described above but when I started using TPFanControl the audible fan noise went away.

The avg temperature is around 53C and the fan is unaudible at a bit less than 2000 RPM.


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Re: T420s Fan noise Issue

2011-11-30, 5:51 AM

Any update from Lenovo? It's been two weeks since Jamez last posted. 


I'm still running TPFanControl, and I wish I didn't need to rely on this third party app to keep my fan under control.


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Re: T420s Fan noise Issue

2011-12-01, 16:27 PM

I also have to use TPFanControl to keep the machine reasonably quiet - I hate fan noise, especially high-pitched noise. I always keep the fan at level 2 (around 2,000 RPM), in which case it is absolutely quiet but a little bit warmer than I'd prefer (as it was posted before: around 50-55°C). The thing is that the next level 3 is running the fan at more than 3,500 RPM and is clearly audible, actually inconvenient (the intensity is OK but the high-pitched noise is not OK).


What we need to do here from my point of view: fix the high-pitched noise (you've managed to do it with X1 and the problem was much worse so why not with T420s?) and change the third fan level to around 2,500-2,700 RPM. Once this is done, I believe everything is going to be OK!


What I'd like to achieve: quiet yet active cooling at 2,000 RPM most of the time (inaudible), sometimes 2,500 RPM, keep the temperature under 50°C.


The only machine from Lenovo I've had similar problems with was the X1 but (as I've mentioned and tested for the Czech Lenovo office) the problem was almost completely solved by BIOS update. So get up your fannies and start doing something! ;-)

Lenovo ThinkPad T440s (i5-4300U, 4GB, Intel HD 4400, 256GB SSD, WWAN)
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