Sourcing really good thermal pastes is a real challenge at the moment. The DOWSIL TC-5888 and TC-5550 are prime examples of the frustration that modern supply chains or manufacturers’ unwillingness to supply can cause. Although these highly specialized thermal pastes are indispensable for demanding applications, their availability is like playing the lottery. On the one hand, they are often not available from established distributors and on the other hand, the China store tempts you with seemingly low prices – but beware: what you get there is usually a sad game of chance.

Sometimes you actually get an original product which, with a bit of luck, will even be delivered. But often it is a potentially dubious substitute – inferior, contaminated or simply not what it says on the packaging. Quality controls? More likely a planned fake! What’s more, there is hardly anyone to contact in the event of problems and returns are practically impossible. The biggest annoyance, however, is the waste of money, time and resources: you wait weeks for a delivery only to find out at the end that the product is unusable. If you are able to do so at all.

At a time when precision and reliability are essential, sourcing such critical materials is simply chaos. Conclusion: Anyone who relies on DOWSIL products should either dig deeper into their pockets or be prepared for a good dose of frustration. Or they should switch to an alternative, which I write about often enough.

Although the search for a genuine replacement seems rather impossible. Well, almost. Because today I’m testing two pastes, both of which come from the same store and appear to be reasonably priced. I would like to take this opportunity to thank our forum member

Even during the first practical use, my colleague had his doubts because the DOWSIL TC-5888 did not perform as shown in my database charts. Because what this paste delivered was actually only a shadow of what it should have delivered. The stated 5.2 W/m-K is actually just a bland joke.

Here are the final temperatures from his test and you can also read the whole thing again in the forum, because he really put a lot of work into it:

And now? Now it’s my turn to put both pastes through their paces again and then compare them with the respective originals. And let me spoil it for you: there will be an absolute precision landing and a total crash landing, which I will of course prove and document.