Best thermal pastes in 2021 ?

[lexluthermiester]

I didn't bring it up again.

No worries mate, was only giving you a bit of light-hearted teasing..

 

[VeqIR]

The runny pastes get squeezed to such a thin layer over time that their performance is irrelevant because there's so little of it between the die/IHS and the cooler base plate.
The viscous stuff is often more conductive but gets squeezed out less, so its performance over time remains largely unchanged.

• Long-term paste performance should be negligible because eventually the mounting pressure squeezes nearly all of the paste out of the sides anyway.

Theoretically that should be a good thing. In the sense that less TIM but just enough to fill in the shape of the gaps exactly would be perfect. In other words the plates get closer and closer together, squeezing out excess, and any paste in the "valleys" between various local peaks and imperfections should remain and provide contact. I'm just not sure why in practice it doesn't work as well as it seems it should. My guess is that perhaps there's also some separation of oil that happens when this thinning gradually takes place, such that the filler material is not of the original paste consistency. What do you think? Perhaps it's because of some small movement / expansion / contraction that ends up in temporary air gaps instead of perfect contact?

 

[Shrek]

No worries mate, was only giving you a bit of light-hearted teasing..

It's hard to know with the written word; I'm sure I'm not the only one with this problem.

 

[freeagent]

It's hard to know with the written word; I'm sure I'm not the only one with this problem.

I’m terrible too. I read into things waay to much at times, and I am sensitiff/insensitiff too.. meow. But still a jerk sometimes, not sure why.. maybe my sore back lol.

 

[Shrek]

Perhaps it's because of some small movement / expansion / contraction that ends up in temporary air gaps instead of perfect contact?

I think you are right here, the end of the heatsink is hotter than the rest and so expands out, putting pressure on the center of the CPU; then when it cools it flattens back driving paste out.

I attach a diagram from the Semikron application note.

 

[lexluthermiester]

It's hard to know with the written word; I'm sure I'm not the only one with this problem.

I’m terrible too. I read into things waay to much at times, and I am sensitiff/insensitiff too.. meow. But still a jerk sometimes, not sure why.. maybe my sore back lol.

Yeah, that was my fault, I should have thrown a smile or laugh emoji on the back of that comment. It's kinda what they're there for.

 

[Chrispy_]

I think you are right here, the end of the heatsink is hotter than the rest and so expands out, putting pressure on the center of the CPU; then when it cools it flattens back driving paste out.

I attach a diagram from the Semikron application note.

Interesting; Thermal expansion and contraction acts as a very slow paste pump...
This could be why laptops need repasting more frequently than desktops - the temperature deltas between idle and load are much larger, increasing the stroke of this pumping action.

Desktop coolers typically use solid baseplates with a lot of material that are mechanically rigid and likely remain flatter under thermal cycling, and their load-idle delta is probably ~40C
Laptop coolers are definitely way more flexible and and with many laptops operating at 95C by design we're looking at maybe a 60C load-idle delta.

 

[Pictus]

Migliore pasta termica 2023 - Roundup e test migliori paste termiche

Quale è la migliore pasta termica 2023 per pc, cpu e overclock? Roundup, classifica, test, benchmark e temperature migliori paste termiche.

albestech.com

 

[CyberCT]

I think you are right here, the end of the heatsink is hotter than the rest and so expands out, putting pressure on the center of the CPU; then when it cools it flattens back driving paste out.

I attach a diagram from the Semikron application note.

So if my CPU stays cool enough (die temp doesn't go past 55C under high CPU usage gaming loads) there isn't as much expansion / contraction going on, minimizing this effect? Honestly I've had past on CPUs that I haven't changed 5+ years and they're still running cool I always have AIDA64 running in the background to check.

 

[Shrek]

If one is running below 55°C max, one almost doesn't care if one loses thermal paste or not.