This is mostly urban legend. You have to really get ridiculous to apply too much thermal paste but you can use too little, so no reason to err in that direction in mass manufacturing. https://www.youtube.com/watch?v=EUWVVTY63hc
> you can use too little, so no reason to err in that direction in mass manufacturing
Exactly. The thermal conductivity of air is 0.026 (W/m/K), your average thermal paste (non-metal) is at 2. For manufacturers it's way better to guarantee uniformly meh conductivity by using too much thermal paste than risking air bubbles by using too little. Most manufacturers will lean this way when they don't just use those POS thermal stickers.
Same with average versus silver: silver provides a gain but a limited one, and it's conductive so you have to make very sure not to leak any onto circuits or you risk a short. That's why manufacturers don't bother.
Is there a meaningful impact of the thickness of excessive TIM? I suspect the answer is no given the clamping power of the mount will get the paste down to roughly a consistent thinness even with over-application.
What about any excess TIM off the edges drawing heat away from the heat pipes/cold plate?
