How to apply liquid metal for CPU and IGPU laptop.

[alci.arto]

Hi,
I am just wondering how I should apply the liquid metal when the CPU and IGPU are on close position on an intel chip.

For example:
https://hothardware.com/gallery/Article/2469?image=big_skylake-core-i7-6670hq-skull-canyon-nuc.jpg&tag=popup


Does it even do something if both surfaces (cpu/gpu) get in contact via the application of the liquid metal ; or it is imperative they don't touch each other ?

I plan to apply electric tape all around it, shall I emphasise their separation on the board as well or not, thanks!

 

[CountMike]

In one word, carefully and only on one side after very thorough cleaning and de-greasing. I don't fully understand " or it is imperative they don't touch each other ?", cooler body has to be fully in contact with processor and TIM.

 

[n0ns3ns3]

you should apply VERY THIN layer of liquid metal on both CPU and iGPU.
if the result of your application is that the liquid metal "connected" - you've done it wrong.
electrical tape is not the greatest idea - clear nail polish around the dies should do the job of preventing the excess of liquid metal (which shouldn't be there if applied correctly) to spread beyond the CPU.

 

[alci.arto]

@CountMike, to be more clear, basicly, what I was wondering is if putting a uniform layer of metal liquid that covers cpu and igpu together, as there are in a very close position, was dangerous or not.

@n0ns3ns3 So it is dangerous, thanks for the intel, this is gonna be challenging, they are so close to each other, I think I will just put some gc extreme thermal paste on the gpu, and put liquid metal on the cpu to avoid risks.
What you mean by a clear nail polish exactly, I ain't too familiar with the metaphor (not english native speaker), thanks.

 

[CountMike]

Yes. t's dangerous to have LM on anything but surface of processors as it is highly conductive and may make a short if it leaks anywhere. Some may have a problem with aluminum coolers and etch them badly.
Nail polish is what (mostly) women apply to their finger and toe nails.

 

[n0ns3ns3]

that's nail polish
https://modestyplusglamour.files.wordpress.com/2012/12/clear-nail-polish-isolated-on-white.jpg?w=698
You don't really have to use liquid metal - a decent thermal paste like Arctic MX-4 would do almost the same job without any risks. couple of degrees will not make any performance or noise difference.
Laptop CPU will continue to throttle under very heavy load anyway.
I'm saying it from experience as I played a lot with those things.

 

[BFG-9000]

If your laptop cooling system is made of Aluminum where it contacts the dies, then most liquid metals (which are largely based on Gallium) will dissolve it. If it's made of bare copper, then there are many reports of the liquid metal appearing to "dry up" as it is actually absorbed into the copper, so it often requires a reapplication once (and you only get like a 1/4mL). That's why it's best to use only nickel-plated metal surfaces or bare silicon with liquid metals.

As said, with a laptop the problem usually isn't getting the heat off the die but getting it from the very limited surface area of the fins into the air.

In any case bare dies generally work fine with even very thick pastes like AS5 or PK-3, because the reduced area compared to heatspreaders still allows it to be easily squeezed out into the very thin layer needed for best performance.