Arctic (formerly known as Arctic Cooling) has been pushing out cooling products for 20 years, but has not released a new thermal compound since late 2010. That is about to change. Over on Amazon's UK portal, there is a retail listing for a brand new MX-5 paste.
Unfortunately the listing is short on details—there is no mention of viscosity or the paste's thermal properties. However, it does share some traits with its popular predecessor, the MX-4, those being that it does not contain any metal and is not electrically conductive, so a sloppy application won't short circuit your PC (see our guide on how to apply thermal paste).
A single application on a CPU or GPU is also good for eight years before needing to be cleaned off and reapplied, according to Arctic's description. The same is true of Arctic's two previous thermal compounds (MX-4 and MX-2).
It will be interesting to see how the MX-5 fares compared to the competition. These days, Arctic is going up against some stiff competition, both new and old. Pastes such as Thermal Grizzly's Kryonaut and Innovation Cooling's Diamond 24 are popular options. As for myself, I still get good results from Tuniq's TX-4 compound.
One thing working in Arctic's favor is brand recognition, at least among enthusiasts. The company's MX-4 compound remains a popular option, despite its age—it debuted way back when you might have been pondering whether to build an AMD Phenom II X4 or Intel Gulftown system.
You might be wondering if the kind of thermal paste you use matters, and the answer is yes. From their cooling properties to ease of application, there are differences between grease, liquid silver, and thermal pads. They all aim to do the same thing, though—improve cooling performance.
What you can't see when looking at your CPU's integrated heatspreader (IHS) or your heatsink are that the surfaces are not actually completely smooth. There are microscopic nooks and crannies, and thermal compounds help fill them in for a better contact.