Thing is, I would like to get a VII for my new Linux build. The fact that it’s a “fallen” pro model and not an OMG-gaming!!!11eleven one plays a big part (even though I don’t currently have a use-case for it besides gaming), it’d be a high-end card for once, it’d not become obsolete because of too little VRAM, like many of its predecessors, and it’d actually be able to drive my 4K screen.
But there are rumours that it’s been cancelled, after just half a year and I’m weary of spending a lot of money on something that won’t be receiving support from the manufacturer (because it’s EOL) or the community (because not many people have one).
Is this a legitimate concern? How have AMD “niche cards” fared in the past (in general and under Linux specifically)? Or is the VII similar enough to the Vega 64/56 (of which there are legion) that all driver improvements would trickle up anyway? (Phoronix still show lower than expected performance relative to the other Vegas in some recent benchmarks, for example.)
The other option is a reference 5700 XT, which still … has teething problems (even under Windows), a sub-par cooler, and is still quite expensive – I’d be lucky to snag one for MSRP here. Yes, I could wait – for custom cards, for Big Navi, for Godot. But that’s mean letting the system sit unused in a corner …
It is the last of the GCN cards, but it is similar enough to the other GCN cards that the same drivers work. Also, AMDGPU which the VII uses is open source, so at the very least, drivers still should be buildable for the forseeable future, unlike the previous radeon proprietary drivers which I do not think are available for modern kernels(could be wrong).
In the end, I think it will have shorter total support then say the r9 290, but I really do not know at this point.
I haven’t really heard about and news outlets giving their opinion on this but here is what I think. AMD giving their new cards the 5700 and 5700xt designation makes me think that they are going to be focusing more on top of the line halo cards this go around, much like the 4700 days. With them going back to their older naming conventions makes me think that there will be many more versions of the 5700 line. So if you can I would hold off a few months. Word is there are bigger and better cards coming later this year.
If you can’t or don’t want to wait then I wouldn’t be scared to go with the radeon VII. It is a good card and I don’t believe you will have any issues with support for years to come. Maybe others here on the forum can speak to that a little more than I can.
I can’t answer the Linux driver concerns, but be aware that even the Radeon VII’s cooler stinks too. It just looks and feels better that the usual AMD blower junk. But it’s useless at actually reducing heat in any meaningful way. 
Forgot about OCiing if that’s your thing, unless you water cool it. The VII really blossoms under water and turns into a beast once you crank the core / HBM up. The benchmark numbers show quite an increase from stock once you get over 2000mhz core. As usual with AMD, heat is the main problem to solve.
I think it will continue to be supported drivers wise but won’t receive gaming optimizations at he saem rate as the rDNA cards. That card is incredible beyond gaming applications, so there is still demand for it. It is no longer in production and I’m not sure where you would find one beyond the used market.