What makes you so sure?  I have a 7970 that still plays EVERY game on Ultra maxed out.  Hell the 7970 GHz Benches like a 780 now because of how forward-thinking AMD is with their architectures, and the 7950 beats a 680 when it used to lose to a 670.

Who is to say that in 2 years the 290 couldn't be benching close to a 980 while the 290X trades blows with a 980 Ti?   By no means am I saying it will happen, but weirder things have happened...

Oh and your VRAM comments make me remember 3 years ago when everyone said "You don't even need any more than 1GB of VRAM anyways!"  Now all of those 580's are struggling to keep up with 6970's...

All I'm saying that VRAM will be the least problem of the cards. It just doesn't have such a profound effect you want to make it sound like. Please read the article you posted for yourself. The effects are minimal and in the single digits. You sound like someone who wants to make a Pentium III PC faster by putting more RAM in it.

Your 7970 plays every game maxed out on 30 fps. That's no standard. 60fps or go home. Your 7970 is not able to do that on current games, hell even the 980 struggles with that at in certain extreme cases. 970 barely keeps the status quo today. It won't be able to play any games properly 2 years in the future even if it had 200GB of RAM and a 1025 bit memory interface.

And that the 290X will ever come close to the 980ti is absolute garbage. Do you even know what you are talking about? Big Maxwell will have about the same RAM and memory bandwidth  as the 290X while massively surpassing it in everything else. Please educate yourself before making such "predictions".

@vivster

your assumption that upcoming games won´t fill 4GB of VRAM is false.
my voxel-global illumination renderer alone is memory-limited by itself to give an example.
actually anything with voxels behind will get memory-limited pretty fast.

if you don´t know what a voxel is - it is like a 3D pixel.
while pixels consume O(N²) memory, voxels consume O(N³) memory - so that you know where the limitation comes from.

however this issue the GTX 970 has won´t effect real-world performance that dramatically anyway i assume.

You've got to be kidding me.....

My point wasn't that no game will reach it. My point was that it's the exception rather than the norm. Voxels are a great examples for this because barely any game uses them in a sufficient manner to fill up the RAM. It's easy to fill up the RAM, and it's just as easy to disable features to reduce RAM consumption. For example ultra texture quality that is barely an improvement but doubles consumption. See Shadow of Mordor.

The more important point was the one you also acknowledged; that RAM size and bandwidth limitations are not as big of a factor as OP likes it to be.

By the time that voxels and high quality textures become more prevalent we will have 512bit memory interfaces and at least 6gb RAM as a standard for performance gaming rigs. Now and in the future the biggest bottlenecks will be in the chip and not the RAM.

Well, thank God I decided to wait for AMD to make their move, even if that means waiting until June (Grrr! Seriously AMD?).

Nvidia announced that this is a hardware limitation. They cheaped out on the memory controller which is causing the problem. You basically have a 3.5 game card.

All games using 4GB in the future will have frame pacing issues, on top of lowered performance, but if you plan on keeping your card for over a year it has no future proofing. Nvidia press statement is reporting an average performance delta to hide the problem. Don't be fooled by this as the instant performance hit leading to lower than average results actually results in sporadic frame times, screen tearing, and judger for gamers when it happens. For games that will use 4GB in the future this card will be SOL.

AMD GPUs age really damn well but NOT that well ... 

It's bad enough that Nvidia has to throw vastly much more transistors to beat a sizably smaller AMD part it would be humiliating to see a new 550mm^2 part having issues outing an old 440mm^2 part. 

Nvidia said they are working on a patch for this, but whoever wants can go get an AMD card and enjoy shitty drivers.

These guys knew about this and still sold it as a 4gb vram gfx card without telling anyone, consumers found out about this themselves?......ok then