Arctic MX-6 ULTIMATE Performance Thermal Paste - 4 g with 6x MX Cleaner20% Better Performance With its improved composition, the ARCTIC MX 6 has a measurably lower thermal resistance than the MX 4. The basis for calculation is the temperature difference between the cooler base and the heat source (in C) in relation to the applied heat load (in W), which also results in the unit C W. The higher the thermal resistance, the worse the heat can be transferred through the TIM layer. Thermal insulators, as an example, therefore