http://www.reddit.com/r/buildapc/comments/2tu86z/discussion_i_benchmarked_gtx_970s_in_sli_at_1440p/
http://www.pcper.com/reviews/Graphics-Cards/Frame-Rating-Looking-GTX-970-Memory-Performance
http://www.reddit.com/r/buildapc/comments/2tuk1f/gtx970_35gb_vs_over_35gb_usage_and_stutter/
http://www.reddit.com/r/pcgaming/comments/2s2968/gtx970_memoryvram_allocation_bug/
But since a very slight amount of games might use 4GB
It's not just about what they can or can't run right now. It's about card longevity. MANY people (like me) bought the 970 under the pretense that it would be one of the best multi-gpu solutions for 1440p/4k gaming. SLI'ing the 970's is a fucking disaster, as documented above.
But it's stupid to punish 1 company while 2 of them are basically are doing the same thing.
Again, you're being apologetic towards Nvidia. Selling a 3.5GB card as a 4GB straight up hardware, will never be fixed by any driver or software update, then initially refusing refunds and making third-party retailers take the hit is NOT the same as selling an 8gb card with the potential to hit 8gb someday.
That would be like equating buying the gtx 980 because I get way over 60fps in most games, 70, even 80, but I can only see 60fps since my monitor's refresh rate is only 60hz to a card that's advertised as playing at 60fps, but you only get 50-55fps. It's not the card's fault. It's a hardware limitation - the refresh rate on the monitor.
There's a huge difference between the two situations, in terms of real-world performance and card longevity, and I can't understand how you could equate these two things, they're not similar in any way.
Not making use off all VRAM on the card.
Again, this is not the case, even you explained it yourself. The 970 can use all 4gb, but accessing the last 512MB causes stuttering. I could use the r9 295x2 to play any game on the planet at 4k, and even if I were only getting 40fps, I wouldn't see any stuttering since the ram required to run/is being used isn't compromised.
This is the thing that most people don't seem to understand at all - it's not just a problem with the 970 being a '3.5GB vram card', it's a problem with performance AFTER you hit 3.5GB+, which makes most games unplayable.