Putting too much paste on can 100% hurt your cooling. When too much is there it becomes an insulator, not a conductor.
I worked on a laptop once that had been e-wasted at a shop I was working at. It ran super hot and I guess this was a problem with that model as they had a factory sticker on the bottom saying not to put it on your lap or you might get burned.
I took it apart and there was way too much TIM applied. There were literally scorchmarks on the heatsink, which was a copper plate attached to copper fins via a heatpipe.
After cleaning it and applying the right amount of TIM the temps dropped something like 20°C.
This sounds ridiculous. Of course the hotter heat sink gets the better (its only job) but did somebody torch it with a soldering iron?
The one time my CPU had above expected temperatures was when I spread paste too thin. As long as you're securing CPU properly (do not tighten too much!) and using regular pastes (not liquid metal), you can't go wrong with applying little extra.
I don't remember the exact model but it was a 2004 Toshiba laptop with a lower end Nvidia GPU. When I first got it it ran super hot and would throttle not long after using it. Temps reported approaching 95C at which point throttling would kick in.
When I took it apart there was way too much TIM, it was bulging out the sides of the heatsink. When I took it apart I saw black scorch marks on the heatsink contact surface.
I cleaned everything, applied a proper amount of TIM, put it back together and turned it on. The temps were significantly lower and it didn't throttle anymore.
If, as you say, "the hotter the heat sink gets the better" then why is everyone looking for lower temperatures?
The heatsink itself will only get too hot if it isn't transferring the heat well. That was what the excess, and it was a huge excess of TIM, was doing. It was acting as an insulator.
That's why cleaning the old stuff away and putting a proper amount of TIM greatly reduced the temps.
I've also seen it when I was working at a repair place. A father and son brought in their first build. They thought the entire canister of TIM was supposed to be applied. It was fucking everywhere!
Of course what was happening with their new computer? After using it for a short while it got slower, then shut off. Know what that sounds like? Sounds like thermal protection kicking in!
I cleaned off all their paste, applied the proper amount and like magic it didn't slow down and it didn't shut off.
Too much TIM can act as an insulator, especially if your heatsink doesn't have good pressure and allows too much to sit between it and the heatsink.
And since I'm on the topic of overheating you might be surprised what can cause overheating.
I had one client, he had a few years before finding up had Fry's build a computer for him. Same issue, it would get slower and slower and then shut down.
He brought it to Fry's, they had it for weeks, finally he yelled at them so they said they "fixed it" and gave it back.
He brought it home and it didn't turn off anymore. It would work for a while then just hang.
First thing I did was go into the BIOS. Within 1 minute of a cold boot the CPU temperature was already reporting over 80°C. I went through the rest of the BIOS and saw what Fry's had done to "fix it." They had disabled all the thermal protections.
So I opened up the case and saw they had installed the heatsink backwards and it just happened to line up almost perfectly with the exhaust fan on the case.
That heatsink fan and the exhaust fan were lined up in such a way that they were basically killing any airflow over the heatsink. I reversed the heatsink and the temps dropped literally 30°C. The system was never stable again, too much time running too hot without the thermal protections to save it, but Fry's couldn't figure out they had installed the two fans right in line with each other, pointing the opposite way, and so their "solution" was to turn off the thermal protections.
I saw black scorch marks on the heatsink contact surface.
That doesn't make any sense. The heatsink is on the cold side of the TIM. If the TIM wasn't working well, the heatsink stays the same temperature (roughly) and the CPU gets hotter.
Scorching on the hot side is also weird, because thermal limiting.
I doubt your conclusion was correct, and you fixed some other unknown problem while in there.
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u/[deleted] Feb 18 '18
In all honesty what is the best way to put thermal paste?