I hope you didn't put the grease on the GPU... you're not supposed to do that...
Clean out the heatsink. For some reason, a lot of people here seem to think that switching thermal greases will cure any kind of overheating problems (not being derogatory- that's just my observation). To put it simply: It won't.
Clevo notebooks (and in fact, almost all notebooks) do not have overheating problems from the factory. The reason people have problems is because they don't maintain them properly.
The reality is that the difference in performance of thermal compounds is 1-2*C at most. Any more than that and the effect is due to other factors.
That is one of the only valid tests that I've ever seen done. No test of a heatsink or thermal compound is valid if the testing is done on a CPU.
You want to stop your notebook's incessant crashing? Clean out the heatsink.