Well like the Scorpio the Neo won't hit native 4k outside the smaller titles, on AMD hardware we'd need a significantly beefier APU than what's rumoured.

Let's hope they be a little more truthful in their marketing than Microsoft has been.

You can't really quantify the AMD hardware that's actually needed for 4k.
Scorpio is a pretty unique part it seems, it will have more capability than Polaris at any rate.

Capable and Acceptable are two very different things.
The vanilla Xbox One is capable of 4k, but it wouldn't be acceptable from a performance standpoint.

Flops has no correllation with resolution.

When rendering a game you have more than just the pixels being drawn on the screen.
The graphics processor literally builds a 3D world.

Increasing resolution will mean that you have increased demands of bandwidth, caching (Speed and Capacity) and other parts of the processor, eventually you reach a point where the slowest part in the chain will hold you back as it has no spare capacity to keep the chain going.
Some parts of rendering have minimal increases in processing demands and resolution won't affect it all, but that doesn't apply to everything.

Typically AMD and nVidia will make concessions in a GPU design in order to get the best price/performance at any targeted resolution, Polaris for instance isn't designed for 4k, internally it's hardware is going to be a little more "relaxed" when compared to say... Vega or the Geforce 1080, it will have great performance at sub-4k resolutions though where it will shine.

I wrote that in the Scorpio thread already but I wouldn't take "4k gaming" literally. If Sony and Microsoft try to push for actual 4k native resolution in games they will brutally overshoot the market (the same thing that happened with PS3 and 360) because 4k TV adoption rate ist extremely low and will still be in late 2017.

Instead, they'll probably opt for something like native 1440p with added effects and 4k output for media. Everything else would be wasted energy because most consumers wouldn't be able to take advantage of it. They'd be stupid to put all resources into higher resolution instead of higher fidelity.

PS4: 1080p @ 30fps
Neo: 1440p @60fps (upscaled to 4k) with added effects

1080p upscaled to 4k, looks very, very good.

Do you watch DVDs on your TV?  Well, those are 480p, and upscaled to 1080p, and how do they look?

My DVDs look horrible on my 1080P LED Bravia. Maybe I'm too spoilt by blu-ray though. Also I believe DVD's native resolution is actually 480i(interlaced) but there were methods available to push for progressive scan on progression scan devices but it was up to the publisher.

You are correct, it's 480i, but most all DVD players now are upscaling (even the PS2/Xbox 360.)

Blu-ray does look better, but it's not 4K either. 

Native always looks better, buy my point is pure digital upscaling 1080p looks really good on a 4k TV, and it's not the visual leap of last gen.

I guess they can launch Wipeout 4k and say Neo is 4k capable and them keep putting the best game they can with 1080p30fps and all the graphics goodies they can and depending of the game upping the resolution.

Would be very good to have everything increased so that everything scale up and 4k is another bonus, but we know that isn't achievable yet, unfortunately.

This. I'd prefer 1080p60 + extra graphical bells and whistles rather than 4k30 and low graphical fidelity.

Not too much really. Only like 399-449$, using new GPU tech like Polaris 10 or 11 and a bit beefier CPU. So somewhere from 50 to 100 dollars more than a PS4 currently costs.

Pal "Standard Definition/DVD" is 720x576i
NTSC "Standard Definition/DVD" is 720x480i
High Definition is 1280x720 (Allot of 720P TV's are actually 1366x768 or 1360x768)
Full High Definition  is 1920x1080
Quad High Definition is 2560x1440
Quad Full High Definition is 3840x2160
The Real Cinema standard 4k is actually 4096x2160.

That's mostly because it's literally a quad-drupling of pixels, retaining the same aspect ratio. - There isn't any weird stretching or scaling going on.

That assumes that Polaris has the capability to acceptably handle 4k, keep in mind it's a mid-range card, it's target is 1080P/1440P and VR.

Now nVidia is struggling to achieve 4k 60fps with it's Geforce 1080 card...
AMD is trying to sell consumers on two Polaris 10 cards verses a single Geforce 1080 for gaming and benchmarks are backing that up, you can't expect a single card to do 4k.

Vega and then Navi will be AMD's "4k" chips. Not Polaris, no idea where this expectation of Polaris doing 4k came from.