Adding another heatpipe to laptop :D

Well its interesting to see how poorly MX-4 performs in a laptop. Temps used to be CPU 80C - GPU 70-75 at max load and now I'm seeing BD PROCHOT kick in at 97C on the CPU, whilst the GPU in actually running cooler at a mere 65C under AIDA Stress Test. This means that heat from the CPU isn't being properly transferred to the GPU, if you get what I mean...

I've been wanting to do this for a long time, but only yesterday did the thermal/silicone/ketone/hot paste come in, whatever the eBay seller wanted to call it. I can read Chinese, and at least it seemed to fit my requirements. It's essentially like thermal adhesive but much easier to remove. It's like the white blobs you see in PSUs, but mine is grey.

This is the old CPU pipe in stock form. Well it used to be black to aid thermal radiation, but I scraped that black muck off and now the copper is exposed.




Aaand this is the final product. The thermos was just there to hold the new heatpipe in place whilst the adhesive settled. Part of the fan casing was cut off to allow the heatpipe to slide into the fan where heat would get dissipated actively by air. I've seen other people do mods where they add identical heatpipe(s!) but end the heatpipes just before the fan, and I don't see how that would help.

The heatpipe was stuck on top of the CPU heatpipe, and stuck to the main heatpipe at the fan. The grey goop is the adhesive.

I'm lucky that the heatpipe just fits in the laptop chassis with not a millimetre to spare. The mothertboard now flexes up a tiny bit to accommodate for the extra heatpipe, and I imagine the heatsink on the CPU is now under higher pressure on the CPU.

Anyways I can happily say that the new heatpipe works fine. Under full load the heatpipe gets uncomfortably hot to the touch, but not quite as hot as the main default one. Good enough, I suppose, for a $2.64 AUD 60 gram of adhesive...

Full load temperatures are now at 85-90C on the CPU, that's a 10C improvement. Still terrible. but it's an improvement. I forgot to take measurements of the GPU lol. WHether it is because the heatpipe is helping in the heat, or the MX-4 is transferring heat better under higher pressure, I don't know. At least it works and mitigates thermal throttling.

Note: Take my results with a grain of salt. The thermal paste on my laptop (MX-4) does not properly transfer heat to the default heatpipe, or at least does it poorly. My mod relies on the heat being transferred from the default heatpipe to the new one. It is likely that a better thermal paste on the CPU would decrease temperatures more. All temperatures were done on stock voltage and without an undervolt.

I know some of you will be sceptical about the thermal adhesive I'm using it. Well I tested it on my parent's 9 year old desktop with the Core 2 Duo E7400, and full load temperatures are only 5C higher than MX-4. One should note that MX-4 does not degrade on the desktop, so I'd consider it an excellent adhesive. :/ It is silicone baesd, by the way, and it is advertised to stay stable anywhere between -50C to 280C

 

That's a nice mod, but why didn't you switch that MX-4 for something at least semi decent on a laptop? Gelid, IC7, Phobya Nanogrease Extreme, Noctua NT-H1...one of those MUST be available in your area....

 

Yeah, Gelid GC extreme is far superior to MX-4.
Phobya too.

Also, have you tried undervolting the CPU?

 

All the good ones are expensive lol. I'm going to do it some time in the future.

Yes I have tried undervolting the CPU, but it isn't going to do any better because the CPU TDP Throttles down to 15W during the stress test.. undervolting during benchmarking only serves to increase performance.

I can't undervolt that damn GeForce 945M. I have to use a custom BIOS to do it. At stock voltages, I can overclock +135MHz on the core and +180MHz on the memory.

 

Well there's a reason they are expensive. Did you expect a free ride? Gotta pay the fare, man.

 

Sorry to tell you this but it's likely your mod is actually making things worse. What you have effecticely done is a heatsource above your cooling solution. With your construction you have made the error that the heatpipe will not cool down as fast and even block your airflow.

Since I got quite some experience from modding my P157SM cooling system let me give you some really good advice. It will likely drop your CPU temps by quite a lot.
- Check your CPU heatsink fit, you can check this by taking off your heatsink and see how much left there is from your Thermal Paste.

if the fit is tight but uneven, then it's time to lapp you heatsink, turorials about this can be found on youtube.

If the fit is bad (which is think it is) go and get a shim from ebay. Solder that shim to your heatsink, use your thermal adhesive or use thermal compound and just press it on the chip. The best performance is obviously when you solder it, or maybe when doing the thermal adhesive ( don't know the performance of it).

Once you've made sure that your heatsink fits properly, go ahead and buy conductonaut. Unlike MX4 conduconaut is conductive, so you need to be somewhat careful when applying, I like to use sctoch isolation tape (sustains 105) around my chip to make sure nothing spills out of the notebook, others use foam, either way is fine, if you want to be on the safe side.

Once you removed your heatpipe mod, added conduconaut, and fixed the heatsink you'll drop your temps down quite massively. I'd take a guess around 75c.

And before you ask why you dropped in temps, it's because you added mass on your notebook. You would probably achieve similair results by spamming those copper heatblocks on your notebook. So when you go ahead and do a proper mod you will see that the upper heatpipe will actually make it worse.

 

This is a crossection of the fan part at the end.


Your right that I'm adding mass. The CPU takes quite long to reach its maximum (10 minutes maybe) and it stabilizes to 90C. The fan exhaust feels hotter (though I highly doubt it is just the placebo effect) but as for airflow I'm not sure. I don't have the instruments to measure it. I'm getting a temperature probe soon. I gamed in Cities Skylines yesterday (Which stresses the CPU and GPU both to 100%) without an undervolt and the CPU managed to keep under 92C, whereas before it would thermal throttle. The ambient temperature was 28C, about 5C higher than last time I played CS. The new heatsink could just be pressing the old heatsink down with more pressure than previously, which could be contributing to better MX-4 performance.

I'm concerned for using liquid metal. My laptop is moved around a lot since I bring it too and from school every day, and I'm not sure if the liquid metal will ooze out and cause a disaster for my motherboard.

 

Well you block the airflow with the 2nd heatpipe, the fact that your space is limited makes it worse. Airflow is so important it's not even funny. I had a thermal throttling stock clocked 4940MX in my notebook running at 3.5ghz throttling down to 3.1ghz due to thermals, now it's running on 78c stresstest @ 4ghz stable (literally doesn't drop a single mhz).

I move my notebook around a lot as well, I don't know where you get the funny idea that liquid metal would spill. Trust me Liquid metal is only attaching to other liquid metal, you need to press liquid metal so that it would even want to stick on your CPU and Heatsink, and once it sticks there it won't run off, ever. Also people use thermal isolation tape 105c from scotch or foam to make sure that if they screw the heatsink on that it won't leak.

 

Thanks for your input. I'll read more about Liquid Metal and make my decision later. I just read that somebody tried liquid metal and the metal just spilled out entirely from the tube. And plus the "Liquid" kinda gives me the impression that it's like water haha. I'm paranoid that I'm going to mess something up or the liquid metal is going to spill or leak everywhere.

 

It is actually. It's behaving like water when we talk about how fluid it is, however it sticks like glue. Liquid metal doesn't like to stick anywhere that isn't liquid metal. You have to press it onto your silicon until it actually wants to bind with it, once you got a very thing layer, you can add a drop and then spread the liquid metal with another fine layer, you'll see that the liquid metal will stick onto your silicon where you have a thing layer and doesn't want to get out of it. That's also the reason why you need to make another thing layer on your heatsink, because otherwise the liquid metal refuses to stick onto your heatsink and bind it with your CPU.

However, as already mentioned, you NEED to take care of your fit, otherwise liquid metal won't do anything. Can you make a photo of your CPU and heatsink just after your unmounted it? Do not clean it, just make take it off and make a picture of it, that way I can tell if your fit is even, uneven or even terrible.

Also, about the spilling, you're correct, this happened for me as well, but only for Coolaboratory Liquid Ultra, the tube and needle are poorly made. Lucky for us, liquid metal sticks to isopropylalcohol, so just take a piece of paper with isopropylalcohol and clean it nice and easy, it sticks onto your paper and you can suck it up with the needle. conduconaut did a much better solution on this one, never spilled anything, tube and needle are good. So I strongly recommend conduconaut, it's so much better than CLU.

 

I repasted it, and again I'm seeing similar results. Temps are reducing to 80C Max on the core with an ambient temperature of 28C. (Normally it is 20C, but I'm in the middle of a heatwave now)

I expect to see the temperature rise soon. :/

From close visual inspection, it looks like the heatsink is sitting evenly, with the exception of the edges of the width of the heatsink where the clips warp it slightly down.

As for all that white muck you can see on the CPU , I cleaned that up. The little rectangle covered by that fluff is actually the thermal pad that separated when I took the heatsink off. I haven't changed it for a long time but iGPU temperatures are fine.

I should probably add that when the heatsink is put on, each time you screw down one screw the entire heatsink shifts a few mm left and right.

Right now, 80C is for both cores give or take a few degrees C. I did a tsress test before and Core 0 was at 93C and Core 1 was eeh, about 80-85 still. It fluctuates a lot. Right after a repaste temperatures are a lot more stable.

 

As suspected, you got a terrible fit. On a good fit, you should barely have paste left on your CPU, but you got quite a layer left.

 

OK, I researched around and I'll first try that copper shim method with MX-4. Hopefully it will increase the mounting pressure between the MX-4. I'm going to need a good fit for liquid metal anyway

Soldering is not an option for me; although I have a soldering iron, it is too low powered for soldering big things like this. It's only sufficient for electronics work

So would I be right in assuming the layout goes CPU Die>TIM>Copper Shim>TIM>Heatsink?

0.3mm copper shims are the smallest I could find. Perhaps I should also buy 0.5mm just in case? Logically, (and please correct me if I'm wrong) if the gap between the CPU die and heatsink is 0.2mm, I'd want something thicker (0.25mm or 0.3mm) to make sure the entire setup is under pressure?

Oh and btw your signature is funny and cute lol (and so true)

 

Switch out MX4 for this paste CM Maker Gel https://www.amazon.com.au/Cooler-Ma...1517304980&sr=8-2&keywords=cooler+master+nano
Its really expensive than USA version.
The tube is really big and can last upto 2 years if you do constant repaste on different PCs.

 

Usually the small die next to the cpu as the same height, so remove that small thermal pad, put a small line of thermal paste on both and try again, its your pad that is screwing the fit.

 

Lol well it seems I'll be getting a new laptop. Everybody in my brother's class is using a laptop (MacBook Pros or Thinkpad E470s it seems. Eheu! Yuck. Poor display and mediocre battery life in the case of the latter) so now my brother want's my laptop to show off to his class. Aaaand I'll be getting a new one. I've chosen the XiaoMi Mi Notebook Pro with the 8250U and MX150. This one is cooled by one shared heatpipe but 2 fans. Unfortunately it seems to have the exhaust design of the MacBook's (where the exhaust vent is small and the hot air is pushed upwards by the display). but reviews say max temperatures are about 70-80 for both the CPU and GPU.

But of course I'll unlocking TDP limits for the CPU if I can, and overclocking the GPU > . Over at TechTablets Chris claims to have his 8250U gain the multithreaded performance comparable to the 7700HQ by upping the TDP limit. Obviously since the 8th gen CPUs have double the cores, it's going to help more than older CPUs

 

That's.. interesting. Can't say it hasn't crossed my mind to do the same.