There are some defective batches among Arctic MX-5 thermal pastes
Less than a year into the MX-5’s existence, the first publicly known flaw is associated with this thermal paste for which it may achieve lower thermal conductivity than expected. This is due to the compound that makes up the paste not holding together properly, and the thermally conductive interface will harden before application, in the tube. Arctic has supposedly already withdrawn these batches from circulation, but one needs to be cautious.
As part of a quality control, Arctic reportedly encountered anomalies in the composition of its latest MX-5 thermally conductive paste. Of course, this could also have been due to complaints from end users (as is often the case…), but we won’t find out now. Anyway, the first option is more viable for the official statement.
The substance of which the paste is composed need not be homogeneous, the oil is being separated from it. As a result, the residue and also the base of the heat conducting medium hardens. This does not even have to be the case when the paste is already in operation, it also occurs during storage in the tube. Increased viscosity naturally means degraded heat conducting properties, as the paste does not get into the crevices on the IHS surface under pressure of a cooler, and in worse cases the density can be so high that the paste is not even properly spread or at least stays in a thicker layer than is optimal from the point of view of heat transfer.
When spreading, the paste can tear and the application process itself is inconsistent with how it is supposed to look like when working with paste. Arctic has also assessed this as a critical condition and no longer supplies such problematic pastes. This should only apply to selected batches.
It is a pity that there is not more detail on this situation and information on how a defective paste could be identified before you buy it. This could happen in the context of a sale, and such bad luck can naturally make life difficult. But you don’t have to return the paste to the store, Arctic will compensate you.
If you find that there is something wrong with the paste (for example, oil separation or excessive hardness), you can ask the manufacturer directly for a new one by showing your proof of purchase. This is not an ideal solution, as you usually need to use the paste right away, but at least it’s not money thrown out the window. You can contact Arctic in this matter on the support page via this link.
English translation and edit by Jozef Dudáš