Is it too early to starting thinking about past Navi? Of course not, provided you're willing to take any and all early information with a few grains of salt. As you might already now, Navi is slated to arrive sometime in 2019. There are still many questions surrounding Navi, but looking even further down the road, the codename for Navi's successor might be Arcturus.
Let's talk about Navi for a moment before getting to Arcturus. It remains to be seen what kind of performance Navi will bring to the table, though rumor has it the next-gen GPU architecture will be more of a mid-range product. Compared to NVIDIA's product stack, it's been speculated that Navi will offer performance similar to a GeForce GTX 1080, at mainstream prices.
Obviously we'll have to wait and see if that is actually the case. What we do know, however, is that Navi is being built on a 7-nanometer manufacturing process. AMD recently said that it's basically going all-in with 7nm fabrication technology for both its CPU and GPU products, including an upcoming 7nm refresh of Vega.
"We have invested heavily in our architecture and product roadmaps, while also making the strategic decision to bet big on the 7nm process node. AMD’s next major milestone is the introduction of our upcoming 7nm product portfolio, including the initial products with our second generation 'Zen 2' CPU core and our new 'Navi' GPU architecture," AMD's Mark Papermaster stated in a blog post.
Papermaster also said that AMD has already taped out multiple 7nm products at TSMC, and that the company has "seen excellent results from early silicon." So far so good, in other words.
This brings us to Arcturus. A forum member and "AMD Linux liaison" at Phoronix brought up the Arcturus codename when a reader asked about all of the numbers involved in modern AMD GPU codenames such as Vega 10, 11, and wanting to see a return to non-numerical GPU codenames.
It's believed that Arcturus will be the first codename under the revised naming scheme. If true, AMD is apparently still looking to the solar system for inspiration—Arcturus is a red giant star in the Northern Hemisphere, and is also the brightest star in the constellation of Boötes (the Herdsman). It's one of the brightest stars that can be seen from Earth, in case you want to dazzle your friends with trivia.