The relationship of the fluidity of a paste (i.e. its flow properties, the opposite of viscosity) and the maximum possible contact pressure of the used radiator construction can be seen by the different radiator structures and the respective results. The consistency of a paste is always a smaller or large spring foot for newcomers, because with increasing viscosity, the paste is then also what is called tough. In general, however, a paste with lower viscosity is much better to handle than a so-called “tough” paste, even at lower pressures, such as those found in Intel’s push-pin fasteners. The interested reader can also read on the handling with heating before using viscous pastes in the thermal paste tutorial. Often only careful heating to just over 50°C helps to get them a little more supple for the job. 
The animation below clearly shows how the thermal paste moves away to the sides under pressure. I will go into more detail later on the relationship between the fluidity of a paste (i.e. its flow properties, the opposite of viscosity) and the maximum possible contact pressure of the cooler construction used. In general, however, a paste with lower viscosity is much better to handle than a so-called “tough” paste, even at lower pressures, such as those found in Intel’s push-pin fasteners. 
