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Comment by trompetenaccoun | Hacker News Reader

>current Fanless cooling solution which tends to degrade after a few years.

What do you mean by that? I've had both PCs and laptops that were completely passively cooled and there was never any degradation.

Lots of different cooling solutions, the issue is there isn't a perfect one that works for all wattage while having no drawbacks. Either it's excessive noise, limited performance, large size, high price, complicated maintanance and so on.

The lofty claims they make are suspicious, I want to see this in action on a high performance chip without any other cooling.

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> fanless cooling solutions which tends to degrade after a few years.

Thermal expansion/contraction between cooler and chip itself "pumps" out the thermal paste which over time degrades cooling performance. If the system is running 24/7 its probably not as noticeable because you don't get the frequent heating/cooling you'd see on a device that gets power cycled often.

Nothing a repaste job wont fix.

Are there designs that don't use thermal paste? As I understand it regardless of solution you need paste or live with significantly reduced conductivity. That goes for any system - fan cooled, liquid cooled, passive,...

Graphite thermal pads are available for consumers (e.g: Thermal Grizzly Carbonaut, IC Diamond Graphite) which offer similar performance (within 5°C) to paste without this issue.

Does Apple use paste or pads in the MacBook air?

Edit: to answer my own question it looks like Apple uses thermal paste but the cooling in the M2 MacBook Air looks extremely flimsey to the point of being almost non-existent. I doubt it will be affected much at all by this.

You're looking for phase change materials (PCM), which soften at the desired operating temperature. Prevents pumping out because it's still mostly-solid.

E.g. https://thermalmanagement.honeywell.com/us/en/products/therm...

>> Are there designs that don't use thermal paste?

Yes. Glue. Paste is for when you might want to one day separate part from heatsink. If you don't care about repairs, it is perfectly reasonable to just glue them together with thermal adhesive.

is it theoretically possible to have cooling paste be jelly like? so it just returns to previous position after cooling down? or its just to irrelevat problem to invest in it?

>is it theoretically possible to have cooling paste be jelly like?

That is already available and used in some Laptops. Look up Honeywell thermal pad.

The problem is as always, cost.

I thought thermal pads are generally thicker and less performant

There are thermal pads that perform equally or better than thermal pastes, due to their design. In particular, something like https://thermalmanagement.honeywell.com/us/en/products/therm... can be better than a good thermal paste like https://www.thermal-grizzly.com/en/products/16-kryonaut-en. The thermal conductivity is improved due to the use of a phase shifting material. Reliability is improved due to the fact that it will naturally return to solid without cracking during heat cycling.

It is, and thermal paste manufacturers need to balance performance against thermal cycling effects.

They seem to be targeting certain devices (laptops and gaming handhelds), not top of the line chips.

I want to see it survive 6-12 months of use in a typical home/office environment with dust.

The immediate thought looking at the design was "this probably has lots of tiny little channels, and those channels are going to get clogged with dust."

In a video from PCWorld they mention that their system has more backpressure than fans, which means you can put filters in the device.

Time will tell, I'm happy someone is pursuing this either way.

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