Update 09/22/2022 3:00 pm PT
Amazon Germany has listed the Arctic MX-6 for a whopping price of €28.75 (opens in new tab) ($23.76 without VAT) per 4 grams.
Arctic's MX-series thermal compounds are among the most popular, among PC builders, and the company's MX-5 is widely considered the best thermal grease that it produces. But earlier this week MX-5 status was changed to end-of-life at the company's website (as discovered by @momomo_us) as apparently it is readying all-new MX-6 thermal paste.
The biggest surprise is that Arctic discontinues its MX-5 just about 1.5 years after its launch in early 2021 and weeks before AMD and Intel are set to start selling their Ryzen 7000-series 'Raphael' and 13th Generation Core 'Raptor Lake' processors with increased maximum processor power. Yet, two images of the Arctic MX-6 packages posted by @momomo_us, a high-tech leaker with a good reputation, indicate that the new thermal grease is incoming.
Arctic's MX-5 thermal grease is comprised of aluminum oxide, aluminum powder, aluminum nitride, polydimethylsiloxane, magnesium oxide and boron nitride. The paste consists microparticles which fill cavities on the surface of CPU heat spreaders as well as cooler bases. Thermal conductivity of the MX-5 is 8.5 W/m-K and it has a temperature range between -40 and 180 degrees Celsius, which essentially means that it's not designed for extreme overclocking. It has a viscosity of 550 pascal seconds, which is below that of MX-4, but it is still easy to apply.
Arctic introduced its MX-5 in 2021, but its thermal conductivity did not change from MX-4 launched in 2019. While 8.5 W/m-K is not bad compared to cheap and mainstream thermal greases, it is considerably below thermal conductivity of market leaders like Thermal Grizzly's Kryonaut and Kryonaut Extreme that are designed with extreme overclockers in mind. In general, the MX-5 shoed very good performance under normal conditions, according to our rating of the best thermal pastes for CPUs around, but it looks like Arctic has something better, which is why it replaces the MX-5 while keeping the MX-4 afloat.
Arctic's MX-5 did not replace the MX-4 and the two pastes continued to co-exist up until recently, even though the new one often performed better than its predecessor. By contrast, the MX-6 actually replaces the MX-5.
We don't yet know exactly what to expect from MX-6, but our hunch tell us that this will be a yet another all-around performer from Arctic, but perhaps designed to better suit the upcoming CPUs from AMD and Intel. In any case, the new thermal grease should be available shortly, so we are going to find out soon enough.