Thinkpads Forum

Happy to read that other people dared to modify their cooling system.

When you opened your tp did you notice the PLL number ?
Because we are trying to find another solution (complementary) :
http://forum.thinkpads.com/viewtopic.php?t=14980

BTW : I saw that if i gamed a lot with my tp (cpu and gpu to max), the cpu temp will stay at about 70°C (with the fan at the same famous medium speed, the same he will not leave because of the hysteresis handling).
So, after gaming (the whole t43p is quite warm because of the high temp during a long time), it's quite hard to go under 46°C and have the fan quiet again. I think the hysteresis is somehow like that :
- low --> medium rpm : 48°C
- medium --> low rpm : 40°C

nrj45 wrote:Happy to read that other people dared to modify their cooling system.

When you opened your tp did you notice the PLL number ?
Because we are trying to find another solution (complementary) :
http://forum.thinkpads.com/viewtopic.php?t=14980

BTW : I saw that if i gamed a lot with my tp (cpu and gpu to max), the cpu temp will stay at about 70°C (with the fan at the same famous medium speed, the same he will not leave because of the hysteresis handling).
So, after gaming (the whole t43p is quite warm because of the high temp during a long time), it's quite hard to go under 46°C and have the fan quiet again. I think the hysteresis is somehow like that :
- low --> medium rpm : 48°C
- medium --> low rpm : 40°C

I didn't grab the PLL number. But, I think I'm going to open it up again because I am not quite happy with the results I'm getting with the copper sheets. The thinkpad will remain silent for a few minutes after startup. The temp is usually around 39 to 40 degrees. It will continue to warm up. When it hits 41 to 42, the fan turns on at a low speed. When it reaches 43 degrees, the speed increases yet again, but it is still below the higher RPM that it used to be. It is pretty cold in my room right now, so I think in more normal temperaturs, the fan will be even louder. I think the north and southbridge are adding a significant amount of heat to the heatsink to cause this slow increase in temperature.

I fixed the problem of the bulging keyboard by shaving a little of the gray pad off with a knife. The stuff is pretty soft.

By the way nrj45, did you remove that pad between the heatsink and the GPU? I didn't. I'm thinking it is some sort of thermal conductor. I really wish I could get the GPU temps.

Have you ever thought about using a resistor to lower the voltage to the fan? IF the fan is running at higher RPMs than it really needs to, then I think lowering the voltage to the fan to lower the RPMs will be safe. After all, the fan is increasing it's speed to cool the northbridge, but in unmodified cooling systems it doesn't cool it anyway. I should have thought of this earlier because that is how I made my desktops quieter. We could even connect it to an external knob to variably control the fan speed. Even better! Disconnect the fan from the connector on the motherboard and hook it up to a constant voltage so that it is always on but at a low speed. I don't know how safe that would be, though...

Edit: I also noticed that there are only two wires running to the fan... the voltage source and a ground. This means that the fan RPMs cannot be monitored; that requires a third wire.

Edit: Edit: After running my laptop at work for 2.5 hours, the CPU temp is at 46 degrees. The fan is also loud again, but I can't tell if it is as loud as before the copper sheets... all I know is that it's too loud. I don't think the fan is tied too closely to the CPU temperature because I have gotten the temp up to 60 degrees with the fan remaining at a very low, almost inaudible speed. It did, however, take a couple hours for the fan to reach this medium/high speed as opposed to less than 10 minutes before. I wonder what is causing it? Maybe Lenovo can tell us all of the components that are monitored for heat.

Well a lot to write :
- my t43p fan has 3 wires
- my fan has the same behaviour (according to temps you mentionned) as yours
- the idea of a resistor is pretty good
- i let the gpu thermal pad in place (i want to be able to remove my homemade cooling system if i have to send my t43p to repair )

About your idea of keeping the same rpm : be careful that the cpu won't get over 80-90°C under load... I mean not the prim95 load but gaming during 3hours in a 25°C room with original voltages powerplay set to max,...

nrj45 wrote:Well a lot to write :
- my t43p fan has 3 wires
- my fan has the same behaviour (according to temps you mentionned) as yours
- the idea of a resistor is pretty good
- i let the gpu thermal pad in place (i want to be able to remove my homemade cooling system if i have to send my t43p to repair )

About your idea of keeping the same rpm : be careful that the cpu won't get over 80-90°C under load... I mean not the prim95 load but gaming during 3hours in a 25°C room with original voltages powerplay set to max,...

Itel specs say the Ms can withstand up to 100 degrees, but I agree with you that 90 is about the max it should get to, just to be safe. Plus, your hands might get burnt if that heatsink gets up around 100 degrees.

One thing that worries me is the northbridge is dumping extra heat right onto the CPU and the southbridge onto the GPU. Do you think they really needs cooling? If I can get the resistor thing working, I might remove the cooling for the north and southbridges to keep my GPU and CPU cooler. Maybe I'll fit a small heatsink onto the northbridge... couldn't hurt. But then again, I haven't seen the CPU temp rise above 70 degrees.

My system is one copper sheet for all chips of the area so they share their heat. If i put a resistor i will keep my system as it is...

nrj45 wrote:My system is one copper sheet for all chips of the area so they share their heat. If i put a resistor i will keep my system as it is...

I knew doing it the easy way would come back to bite me in the [censored]. I think I'll copy your setup, nrj45. Maybe dumping the heat from the north/shouthbridges to just the GPU area of the heatsink would be a good way to keep the CPU temp down, as long as the GPU doesn't get too hot. I really wish I knew how hot the GPU is getting. I would like to test various setups, but I'm afraid fooling around with it too much might break something. I think I'll sleep on it a few nights before I make my next move.

Edit: HA! I just noticed something. If you look at the pictures of the T43 that does cool the northbridge, the heat from the northbridge is routed directly to the GPU, not the CPU area of the heatsink. I think it will be safe. Here is that link again: http://www.8080.net/html/200504/b61415491.html

Lol... My first try was with some aluminium sheets . The copper solution on all the chips was not my first try ...

I really like your idea of resistor... I just wonder how to put a resistor without cutting the wire (the goal is to avoid the ibm/lenovo technicians seeing what i did to my t43p ).

Perhaps order a second cooling system (one to modifiy and one to send the t43p if it has some problem)

nrj45 wrote:Lol... My first try was with some aluminium sheets . The copper solution on all the chips was not my first try ...

I really like your idea of resistor... I just wonder how to put a resistor without cutting the wire (the goal is to avoid the ibm/lenovo technicians seeing what i did to my t43p ).

Perhaps order a second cooling system (one to modifiy and one to send the t43p if it has some problem)

An elegant way to insert a resistor withouth cutting any wires would be to make an "extension" for the fan connector. You would have to find the little male and female plastic connectors that are currently used on the fan connector and motherboard. Connect the ground and the third wire straight through, and use a resistor to connect the positive wire. I doubt that is the method I will use because it seems like it will be way to frustrating to attach those little plastic connector pieces. I'll probably end up cutting the wire and just use electrical tape instead of solder.

A second cooling system would be very nice to have. Where would one find one of those?

No idea. I wonder how much it cost too.

I posted this in another thread but this seems like a better place:

I just bought a T43P 14" about 2 weeks ago. I love the laptop, except one thing...the fan (well sometimes).

When there is no ambient noise in the room the fan pisses me off. Mine seems to pulse. That's really the only word I can think of. If the fan stayed at a constant tone it wouldnt bother me but it hums for exactly 5 seconds and then gets louder for about half a second. It does this when I'm not really doing anything CPU or GPU intensive.

For instance all I am doing/have open is 1 firefox window typing this message.


"hmmmmmmmmmmmmmmmmHMMmmmmmmmmmmmmmmmHMMmmmmmmmm"

If that makes any sense to anyone.

But if I have the TV on, or am in the office, it doesn't bother me at all. Just when the room is completly silent....except for my pulsing fan.

--scott

Does anyone else notice anything like this when using their t43p in silence?

Hrm. I don't know what to make of this but I was gaming a bunch on my T43 and had it set to Maximize Performance power setting. And then I flipped it back to my 'Quiet' setting, which is basically lowest CPU and balanced fan for both battery and AC. But the fan was actually running quieter if I flipped it back to Maximize Performance, where clockspeed was read at my full 1.86 GHz. Not sure what the heck is going on there.

Archinloaf and others, not to be mean, but let's keep this thread going towards sharing knowledge of the problems at hand. We know there is a fan issue, that is why you see so many posts about it.

Again, not to be mean, I know how frustrating it is to have a new T43(p) with fan/heat problems!!!

)

Ruthlessbrad: Yes, we think the northbridge needs cooling -only- because we can reduce the fan speeds (noise) by cooling the chip iteself. This is why we think that there is a sensor around the northbridge that is causing the fan to run so often. The theory is that if we can cool the chip we can slow down the fan.

NRJ, I will have my new system in a couple days and will be sharing all of my opinions on it then. If there is also fan issues with this Tpad I will break it down and keep working on it like the previous one I sent back.


PS: It would *not* suprise me if we found the SOUTHBRIDGE to be connected to these problems as well. NRJ, did you feel how hot the SB gets? Did you try cooling that as well? -You *may* have cooled the SB by accident when fanning the NB.

Rhino :
Yep you're right rhino. In fact i never accused the nb itself because when i put my finger on the chipsetS, i felt they were quite at the same temp (perhaps the nb was a little bit hotter).
Anyway, when i fanned with an external fan, i cooled the both chipsets (they are too close). So it's impossible for me to say which of them (if not both) are triggering the fan.
That's why the copper plate i adapted is covering all the chips (including the sb)
All :
I read that some people feel their t43p quieter if they put the "max perf" power scheme. I don't know why and i don't know what this power scheme exactly does (set powerplay to maxperf and put the cpu at max freq ?). So i will make a test (in this order) :
- in ibm power management : set to maxperf
- set powerplay to min perf
- CHC : allow only the 6x multiplier to keep the cpu freq. at 800MHz even under load.
And perhaps later (when the t43p would be on for 3 hours or more) i will toggle between the 2 powerscheme to analyze the fan behaviour.
Perhaps some other people could also run this "test" and share the results...

BTW : as i'm writing this, my t43p is on for about 20 minutes, cpu temp is at 42°C in a 21-22°C room. At this moment, the fan make about the same noise as the spin of my 5400rpm hdd. In a quiet place it's bearable.

I figured I should give an update. I re-did my cooling setup. I used to have a copper sheet connecting the northbridge to the CPU and a separate one connecting the southbridge to the GPU. I wasn't too comforatble dumping the northbridge heat directly onto the CPU, so I re-did it. I now have a single copper sheet connecting the northbridge to the GPU and the southbridge to the GPU. I also removed the pad and dark gump on the heatsink directly above the GPU. I figured it was inferior thermal compound. I no longer route heat directly to the CPU. Results... nothing different than before. The CPU temps are about the same. In the long run, my CPU seems to hover around 46-47 at idle with the temperature spiking at 66 when running prime95. The fan is just as annoying as before (it also pulses just like archinloaf's). My next step: use a resistor to lower the voltage to the fan. I have a variable resistor that came with one of my Zalman flower heatsinks for a desktop. I will try to fit it inside my lappy. As long as my temps don't get too high, it should be safe. The Pentium Ms can, according to Intel, withstand temps up to 100 degrees.

I mentioned before that my fan only had 2 wires... I was wrong; there are three. So, RPM monitoring is theoretically possible.

Edit: Another update... I powered up the laptop with the fan unplugged, and the screen said "Fan Error" and shut down immediately. The thinkpads must monitor the fan somehow. I hope playing with the voltage doesn't cause a "Fan Error."

I have a new question: What is the purpose of the gray gummysticker (in nrj45's vocab) between the keyboard and the heatsink? I originally thought it was to keep the keyboard from bouncing up and down and perhaps to apply a little more pressure above the CPU. But I read that someone else believed it transfered heat from the heatsink to the aluminum on the bottom of the keyboard. I don't believe it transfers heat because it's so freakin' thick. When you have a layer of thermal pad/compound, you want it as thin as possible; copper transfers heat much better than thermal pads do. Anybody know the answer?

I'm pretty sure that is there for structural reasons and has *nothing* to do with cooling.

I am believe there's no temp. sensor on the chipset. The temp. numbers from the program are just THEORY. Perhaps the system just calculate some math and decide how fast should the fan spin.
Please correct me if I am wrong.

ruthlessbrad : You're right. The grey stuff has nothing to do with cooling... it is just to avoid contact between keyboard and the copper and make pressure (because the copper plate is not perfectly flat after i worked with so i hope that the thermal compound + pressure is enough). I used the same system between the southbridge and the wifi card (but we don't see it because the grey stuff is between them). BTW : the grey stuff was originally between the original cooling system and the keyboard (a big pad, i cut it into many pieces i put here and there)

Nirvana : I think the monitored temp is the cpu's one. But there is a lot of other temp. sensors that are checked in background.

Another things for guys trying to lower their temps : don't use chc to downclock the gpu... It reduces only the freq. but not the gpu vcore. So let this job for powerplay...

archinloaf wrote:
"hmmmmmmmmmmmmmmmmHMMmmmmmmmmmmmmmmmHMMmmmmmmmm"

archinloaf:
The fan issue you are describing was first detected on the thinkpad T40's.
It was remedied by a bios/embedded controller update. Check if there is an update for your machine.

OK Folks, I saw my 1st T43 today. A groupmate just got his T43 with x300/XGA, 1.86 etc ... His fan noise is only marginally louder than my T42. It takes some time to pay attention to it. He told me that the fan becomes audible when he plays games. I ran some heavy duty math code on his machine and nothing much happened. My 1.6 T42 is a little louder (or similar) when doing the same calculations.

My guess isnt novel: the CPU isnt the culprit. But I thought I should mention it as I ran some programs which I would normally run.

Perhaps the culprit is just the GPU. nrj45, when you and I added the copper sheets to cover the north/southbridge, we altered the cooling of the GPU (perhaps made it better). That might be why we are seeing slightly slower fan speeds initially. If the GPU is the culprit, and the north/southbridges are not monitored for temperature, it would be better to remove the cooling for the north/southbridges and improve the cooling of the GPU. Improving it would mean removing the pad and dark gray crap on the heatsink above the GPU and replacing it with arctic silver 5. It might be a good idea to keep a piece of copper between the GPU and the heatsink to make up for the pad and gray crap not being there. I will try this when I can get some more arctic silver... I'm fresh out!

It's been a while from the last update. I switched back to the original IBM cooling setup... I removed the cooling for the northbridge and southbridge. The fan now reaches that annoying level much quicker. After being on for only a few minutes, the fan turns on at a low level. A few minutes later, it speeds up. A few minutes later, it is at that too loud level. I have a new theory... there is a temperature sensor measuring the ambient air temp in the case. The northbridge is hot almost immediately, but the fan does not come on immediately, so I don't think the northbridge is affecting the fan speed. Since I am no longer routing the heat from the northbridge and southbridge out of the laptop, the ambient air temp increases much faster causing the fan to get louder quicker. Again, this is just a theory.

Check out this post: http://forum.thinkpads.com/viewtopic.php?t=11574 This seems to support that theory.

I didn't play anymore with the cooling system... In fact, i'm at school again (no more holidays), and my t43p (while browsing/desktop activities) will never go in speed 3 like he did before. It will stay on level 2. But if i game a bit, it will go in its 3rd speed and never go back (even if i closed the game for 2 hours). I live with it.

I just hope (like a guy mentionned in a post of the thread you mentionned) that in a future bios/embedded controller release ibm/lenovo will adjust threshold of the concerned temp. sensor by 5° to allow a quiet browsing...

archinloaf wrote:I posted this in another thread but this seems like a better place:

I"hmmmmmmmmmmmmmmmmHMMmmmmmmmmmmmmmmmHMMmmmmmmmm"

Exactly as mine, a T43. As you say, if it just stayed on constantly, it wouldn't be nearly as annoying.

Hi people,

I have a T43 2668-F7G and also experience the fan stays on and pulsing problem. I've found a good tool mentioned on thinkwiki.org which allows you to monitor the various temperature readers in the laptop, and allows you to override settings for testing purposes. Needless te say, be careful, but here we go:

Tp4xFanControl 0.18:
http://sourceforge.net/projects/tp4xfancontrol

Good read:
http://www.thinkwiki.org/wiki/Problem_with_fan_noise

This tool confirms that the southbridge is the problem; it always has the highest temp, and therefore controls the bios's fans. For example, fan has now been on for about two hours straight at 4300rpm; cpu=39!, gpu=44, pci(southbridge)=48!

The Tp4xFanControl program package also contains a handy pick showing you the locations of the heat sensors; notice that the southbridge has *no* cooling?!

Hth,

Rubin[/url]

Ah! I forgot, About the pulsing prob:

If you run Tp4xFanControl, you'll notice that the pulses concur *exactly* with the timing interval for reading out the heat sensors. Some smart guy on thinkwiki managed to counter this in his script based linux fan controller thing which I've tested and works amazingly well; pulseless and quiet operation on Linux are working for me with this script, with temperatures arround the 48-50.

If you wanna play with this, visit the thinkwiki link in my previous post.

Hth,

Rubin.

rubin wrote:
Tp4xFanControl 0.18:
http://sourceforge.net/projects/tp4xfancontrol

Good read:
http://www.thinkwiki.org/wiki/Problem_with_fan_noise

or you could just notice the sticky named "FAN CONTRO UTILITY" in this forum.

http://forum.thinkpads.com/viewtopic.php?t=18399

Reviving this topic a little, I search for the FRU:
BM ThinkPad T43 Laptop HeatSink FAN 26R8197
http://i6.ebayimg.com/03/i/08/29/89/ca_1_b.JPG

Indeed it covers the northbridge I didn't such a heatsink would exist. IBM should've shipped all T43 (maybe T42) with that FRU

My T41p fan short was replaced for the FRU 26R9074, I wonder if the original T41/T42 fans run more quietly when spinning.

Also, after 1 year, I would like to know, now that we have TP Fan Control, what's the laptop temperature readings after modding with the copper plates. (att. nrj45, Rhinos)

So wait, this is a newly designed fan/heatsink for the T43's?
I got my T43 shortly after they first came out and I think my heatsink just covers the CPU & Video core.

I looked up that FRU number and it stated that those were for the T43 18xx models. I think all the 18xx have the Intel GMA900 graphics chip built into the Northbridge.

Mine is a T43 2687 that has a separate graphics core (x300), and I think all the 26xx have that FWIW.

Mine came with this fan: 26R9074