Although I've never been conscious of pump out as a problem, and have never reapplied thermal paste, I did use a KryoSheet on a 9800X3D in my most recent build. So far, so good.
But it was a very informative video regardless.
After application, it does not matter whether it becomes solid, which is actually preferable, to diminish the risk that it would flow outside.
I thought ptm was all the rage anyway as it can't pump out and is very very long lasting, but I'm probably outdated in that respect.
Of the latest gen of AMD GPUs, a bunch used PTM.
I’ve had problems with both pump out and other thermal paste aging problems.
The problem is very different across thermal pastes. Some of the high performance enthusiast market pastes I’ve used have started out great and then degraded until I was having problems a few years later.
My feeling is that the engineers and OEMs understand these tradeoffs better than the hobby market. All of those boring pastes that came in OEM configurations but underperformed the latest $20 tube you could buy in the aftermarket were just making different tradeoffs.
The newer pastes have been better for me so far. The person who made this video also does some testing that’s supposed to simulate pump-out and maintains a database of pastes which has been helpful to finally have after all these years of relying on forum anecdotes for everything.
For example, if a consumer is going to periodically (or ever) replace / upgrade their thermal paste, they can get a bump in performance. The consumer that's never going to do that is better server by paste that has slightly lower performance, but lasts much longer.
Does it really simply not stick and is held in place by pressure alone?