P150EM cooling the i7-3940XM

There is a very hot beast under my hood and I heard that Clevo P150EM have flawed CPU heatsinks on almost all their models, I have been trying to cool it with any means possible like adding extra copper heatsinks onto the heatsink itself, sealing the fan to the heatsink with copper tape.

It all works, but it only delays it for a while until it hits 100 degrees and jumps between 90 - 101 in Prime95
I tried Arctic MX-4 and Thermal Grizzley Kryonaut.

Then I have tried to add 15x15x0.3mm copper shim onto the CPU between the heatsink, I had to add two of them because one would not cover the CPU head itself fully.
This helped but again it only delays the initial 100 degree mark in Prime95 torture test.

Does anyone have any experience with this CPU in a P150EM!? A 3920XM is basically underclocked version of it so its the same CPU just lower clock speed.

I also tried looking for undervolt guides, there almost none for this CPU, so if anyone have any experience in undervolting the i7-3940XM since every CPU is running on an overvolt technically.

Also I know that Prime95 puts unrealistic loads on the CPU but I have in video rendering seen these kind of loads but in games the CPU almost never is utilised more than 50%.

This is what the cooling system looks like today except for the GPU it has received minor upgrades but that one is irrelevant here.

 

If you have no air moving over the copper heat sinks they will just gather up heat like you have noted.

 

The fit is actually really good, so for the love of god don't add another shim. I modded my P157SM notebook which had similair temps at stock like yours and ended up with these temps:

Spoiler

Are you using a cooling pad?

The main issue on the cooling system is the heat transfer and the lack of mass. Also you need to remove those copper heatsinks which you have on the CPU and heatpipes. What you're doing is creating an oven, which means you heat up your system by saving the heat in those copper heatsinks. Not only takes is longer to get hot, but also takes longer to cool down.

I added a 3rd heatpipe and bended it upwards to match the other 2 on the CPU to the heatsink, that way you cover the CPU die more, I also added a very small one at the VRMS to the heatsink, also the heatsink got more fins, which i stole from another P15x heatsink and added some more inside the fan casing. You can open your fan case and there you will see that you have a little more room to add mass. You can take another heatsink and cut the parts so that it fits. You'll basicially be building a big heatsink with lots of fins. Warning tho, do not add to many fins, since you will be getting worse airflow, also cutting holes in your case for better air for fans or cimpy a cooling pad is also a good idea.

 

If I remember correctly you also stated your ambient was not normal either. As in you set the laptop outside in cold weather to get that.

 

Correct. It was absolutely ideal scenario.

On the desk with normal ambient temps over very long time and normal fan speeds it would be around 55cish. Still better than the stock 96c I had.

 

Context matters.

I would ask @Khenglish to share his thoughts, as he has the same model laptop and runs his CPU from 4.2Ghz to 4.6Ghz iirc.

 

43° @ 3,98Ghz suuure, we all use laptops while sitting in refrigerators.
It's kind of a whim and it has nothing to do with everyday use of the laptop. Experienced the same story by reading the statements and tests of one of the more famous characters in the scene, whose toy was Tornado f5. I saw the amazing temperatures of cpu and gpu. Everything was so amazing until I saw the cooling stand.
Cooler master u3 plus with 3 noctua fans(12v) with external power supply from the wall...
For most people living in Europe, where there are 4 seasons and assuming that tests are done in winter while keeping the temperature in your home at a level that barely allows you to survive, the temperature of 55 ° sounds like an unpleasant joke. Especially if we are talking about the full use of the processor that works with the frequency @ 4Ghz in laptop.
The funniest thing I saw when it comes to the demonstration of the cooling capabilities of laptops were Alienware tests where the owner placed under his desk portable home air conditioning...
I would really like to see something that will bring down processor temperatures without cutting or drilling in the casing, without additional power sources (except usb), without going outside when the water is ice, without Fn + 1 (9).
I do not want to offend anyone with this post, but I hope that not only I would like to learn/see normal ways or methods and not fanatical frills.

btw

What is status of your clevo Danishblunt? Is it broken still? I am looking forward to the descriptions and informations you promised from the thread
P157SM CPU 4Heatpipe greatness

Regards to All!

 

As already said in the thread, I kinda had to put it aside a bit, since I got myself a P375SM-A now. It's still there, but with a broken board (soundcard got shorted by my mistake, causing the board not to boot). The CPU and 32GB Ram are now in the P375SM-A as well. I'll bring it back to life I think maybe around 1-2 months from now. I'll do the tests with me recording the phone. No stand, no weird fans, nothing. Only my notebook on the table with nothing extra on it.

I did consider modding the P375SM-A, but after seeing the 70s temp on XTU test, I didn't really bother improving to much on that one. Just mainly some airflow things.

 

Inductors don't really get that hot and have no moving parts/sensitive components so no need for that one between the fan and CPU heatsink.

 

the only thing i can think of left to do in your case would be to apply liquid metal paste, like CLU or conductonaut. make sure to use electrical tape, as well as a foam dam around your CPU to protect the surrounding components. ideally, that could net you anywhere around 5-25C compared with conventional paste.

 

The heatsink surface contacting the cpu may be warped (concave), the clue here is big differences between core temps e.g. 15C between core 0 and 1 at idle on my P170EM (same heatsink)

shims can help here but get a minimum 25mmx25mm size to cover the entire die to avoid a gap and uneven alignment between them

The two small heatpipes by my estimate couldnt be more than 30W each, more are needed if you overclock.

+1 to liquid metal

 

Do not use a shim.

The two main problems with the CPU heatsink are the die contact plate is warped, and the radiator dips below the motherboard allowing the fan to suck back in air that just went through the radiator. Lap the heatsink (you need to remove the screw retention plastic to do this), and tape the underside of the radiator to prevent backflow.

 

Taping all 4 sides instead of 3 is a good tip. It really makes a difference.

Sent from my SM-A300FU using Tapatalk

 

What do you mean by "normal ambient temps"?

 

27-29c

 

And 55*C is in idle, right? Can't wait to see the mod outcome.

 

XTU stresstest.

 

Thanks for the responses, I saw someone suggest liquid metal, Kryonaut performs just as well as liquid metal only gives 1 degree better temps at really high contact pressure. Tom's Hardware has done scientific tests of multitude, Kryonaut came out as top contender with the rest of the bunch falling behind by a degree or two.

I removed the heatsinks on the heatpipes, a stupid move from my part I should realised it would just build up heat, this stopped the heat increase over time.
Idle temps around 50 - 55 degrees are normal in room temps with no air conditioning and laptop on a wooden table, it improves with a laptop cooler down to the 40s, while in regular use it can go from 50 - 60 degrees as the CPU seem to love consuming 20 to 30W in regular workloads, I suspect this is because all the patch work that Intel has been doing lately, very little actually runs in the background mind you except Google Chrome.

These temps are normal, I wanted to know, perhaps there was a magic trick that would help improve the cooling methods even more, I have drilled larger intake holes on the plate seeing how Clevo had no brain when they designed the bottom plate on this thing.

I also have Opolar vacuum fans to suck out the hot air much quicker, it helps with the temps as well but its not drastic decrease.
The only thing left it seems is for me to engineer another heatpipe into the design or perhaps just underclock it as its never fully utilised in any games I play or have played.

If anyone know anything about the voltage on the i7-3940XM that be great, I want to know how much you can undervolt it safely.

 

Vacuum only works if the fan is insufficient, otherwise the weak links are generally in other areas of the heatsink

 

I have not seen an undervolt option on any of my ivy bridges on any of the E series Clevos, including 3920XM ES on P170EM and 3940XM on P370EM. Can only add turbo voltage (needed at 4.3 and higher)

The temps sound similar to what I get on 3940XM I have in the P370EM, idles 50s in normal ambient, low load 60s, spikes to 70s, full load about 90C, this is 4.2 max turbo at stock voltage. Mods such as cutting the bottom case for airflow and liquid metal affect the max but I was always a bit surprised the idle would barely budge, even before the heat sink fell apart on me (not enough clamps while soldering other things on) and I had to rebuild it

 

The more air moves through the radiator, the cooler it gets. The cooler it gets, the bigger the temperature difference is. The bigger the difference is, the better the heat transfer is.

No Core Voltage Offset in XTU?


The idle temps might be the same, but fans might spin little slower.

 

If the Vacuum is only able to exert the same pressure or less than the included fan then it's just getting in the way.

 

if the radiator is not capable of holding the energy for the air to carry your wasting your time. You hit diminishing returns very quickly and just wasting your time.

 

True, which is why server fans spin really fast, try to eek out even a small advantage.

It comes down to the balance of the original heatsink.

 

if undervolting isnt possible, that sucks. lowering VCore is like THE number one way to drastically lower CPU temps, were talking a range of up to -20C at identical clocks.

 

At stock clocks, as the clocks go up of course the stock voltage is closer.

The P170EM bios gives more tweaking options if you are not running that already.

 

The Vacuum fans works, I speak from experience while others have seen no difference, really like you said it all depends on the fan.
I see the biggest advantages in high loads and the vacuum fans on full power alongside the laptop fans on full power.