I noticed yesterday that the thermal compound I use becomes very runny once it is heated up. When cold it is very thick, but once at maybe 80 degrees centigrade it is runny and the extra paste starts flowing and running off. I noticed this yesterday when I did a differential pair of transistors with the paste in between them and I was heating the shrink sleeve I had put around them. Then this morning I did a voltage regulator that gets quite hot, soon after switch on the fresh paste becomes liquid... So.. is it normal or did I buy junk ? It is a tube, supposedly made in Germany, bought from ebay... Thank you !