Fudzilla is reporting that AMD's Navi is not a high-end GPU, but rather, a 7nm replacement for Polaris.
https://www.fudzilla.com/news/graphics/46038-amd-navi-is-not-a-high-end-card
AMD Navi is no high end GPU
We have been sitting on this piece of information for a while, but maybe it's the right time to share it with you. Navi 7nm the 2019 chip will not be a high end GPU, it will be a quite powerful performance/mainstream chip.
Think of it as the Radeon RX 580 / 480 replacement. It will be small, and is likely to perform as well as the Vega 14nm that shipped last year. In the Nvidia performance world Navi should perform close to Geforce GTX 1080 which is quite good for the mainstream part but probably on part of the mainstream part planned after the high end part.
AMD won't have anything in the high-end space faster than Vega between now and end of 2019. In GPU world this is eternity. This is the product where Radeon Technology Group really spent some time to go after this highly competitive and profitable mainstream / performance market
The new Navi 7nm mainstream chip would bring much needed advanced to stay competitive and add some Ray Tracing acceleration elements in the chip too.
The earliest we would expect a Navi successor, a real high end chip, would be at some point in 2020.
AMD is also pulling some of their Zen architecture team into the Radeon Technologies Group to help out with future GPUs.
https://pcgamesn.com/amd-zen-next-gen-radeon-graphics
AMD have confirmed they've pulled some of the Zen microprocessor team into the Radeon Technology Group to give their next generation of graphics silicon a boost in frequency, power, and performance.
Suzanne Plummer, CVP of the Radeon Technologies Group, explains how they were using some of the processes that went into making Ryzen a success to help give new Radeon hardware a little helping hand.
But not only are they taking some of the methodology, it sounds like they've also brought in some of the actual people from the Zen team to help Team Radeon make the next AMD graphics cards genuinely competitive.
"A lot of what we did in Zen was trying to push well beyond what we thought we could do," says Plummer, "and I think that is something we're trying to do in the graphics space as well to make a bigger leap forward.
"We've pulled in some of the expertise from the microprocessor cores team into the graphics team, kinda helping with our methodology, and improving our frequency and our performance and power. And just taking the best that we have already developed in-house and trying to make sure that we're using the same improvements across the company."
It's not clear whether Plummer is referring to the Navi architecture when she's talking about "a bigger leap forward" but she could well be talking about the next, wholly new AMD architecture. Given their
leapfrogging design teams we know that they're already working on the post-GCN generation of graphics silicon
Navi GPU = Polaris successor
Next Gen GPU = Vega successor and GCN successor
I think PS5 and next Xbox will use many of the elements going into the new GPU design, even if the the new console GPUs are somewhere between Navi and Next Gen -
Neither Sony nor Microsoft will want to miss out on that tech.
Note: I wouldn't worry about the exact release dates of Navi and Next Gen GPU on this roadmap, it's more than 1 year old, at least.
Also remember PS4 Pro came out in Fall 2016 with a GPU mainly based on Polaris, which launched for PCs earlier that year, and PS4 Pro GPU had a couple features only found in Vega so far, which launched Autumn of last year, and even Xbox One X GPU didn't have these things, like double rate fp16.
Bottom line, if PS5 and Xbox Next launch in the Fall of 2020, they will likely have elements of the next GPU architecture, and also possibly having the extra power/performance that 7nm+ will have in late 2020, over first-gen 7nm in 2019/early 2020.