Please read this post entirely, it will help clear up a lot of misinformation...
- Vram is best considered to be the fuel tank of the GPU. It can only hurt the performance of a GPU if the fuel amount needed is not enough. It cannot "Increase" performance. Period.
- A few games fill or almost fill the Vram (Fuel tank) because they can. It does NOT mean the game needs all that Vram to work. Crysis is notorious on this. It will pack a lot into your Vram because it does not have the same "Controls" as the newer releases do. My point in this one, just because your Vram is close to or is maxed out, does not mean your game is being effected by this in any way. It may just be a saturation of the Vram.
- One other thought on this... Think along the lines of your Computers RAM. Vram works very similar, if you surfed the web or have a F@H project working in the background, stopped it, the Fuel Tank has not been flushed and at times will stack or add the Fuel for your game in/on top of the not yet cleared Vram. Or say even a 3DMark11 run... So like System RAM, your system should be shut off (Only to guarantee 100% accuracy of what tools are able to show you) for no less than 15 seconds... Turned back on and then go into the game of your choosing to see the Vram Usage... Keeping in mind that a few games will saturate the Vram available giving uninformed users the impression that they have maxed out their Vram. And that many times the system "Stacks" Vram. In reality.. Only a system that has been shut down, goes straight into a game/benchmark reflects "Closer to reality" Vram usage.. Back to back test runs can suffer from the Vram not clearing itself and stack all or portions of the previous usage with current usage...
- Nvidia has worked extremely hard at giving us, the end users, a better gaming experience. Think about this for a second... How many threads would you see in a given month when the 8800's/9800's/200's and yes even the 400 series cards are the current gen card... And we would hear about jittery video, or stuttering ETC. Now think of the 580's, how many times comparatively did we read that. And now the 680's... That is correct, hardly at all comparatively. The reason is quite simple, but confusing... Nvidia wants you to have a free flowing of a gaming experience possible. So the drivers today will actually take control of your Game setting (well kind of) through the Nvidia Control Panel when needed. Instead of maxing the GPU out, it balances the GPU(s) to give you a free flowing performance (To a degree much greater than in the past). In a nut shell, if you have a 1.5Gb 580, you will see 1.49GB of Vram usage where as say the 3GB 580 would see 2.2Gb of usage. This is where the Vram can actually hurt performance. As there is not enough to offer the free flowing gaming experience as the 580 3GB card does. However, those not aware of this (Running lower Vram cards 500 series and lower) "Think" their card is more than enough as they hardly ever max out their Vram...
- At this time it seems that Nvidia, with all the technical changes, has improved on the performance/utilization of the Vram. My thinking (Not to be confused with facts as we are all still early in the fact gathering) is those with 2.5G Vram and going to the 2.G Vram 680's will see the Vram GPU comparison performance be a draw. And experience a healthy performance increase due to the pure nuts and bolts and scale-ability these 670/680's have. My performance/utilization opinion based on limited information at this time...
1.0G Nvidia GPU's users to the 680 2G is like a 1.5G jump.
1.5G Nvidia GPU users to the 680 2G is a 1G jump.
2.5G Nvidia users to the 680 2G is a draw.
3G Nvidia users to the 680 2g is a LOSS of .5G.
3D brings a whole new element to the debate. AT this time, I think there is no choice but to go 4G GPU's for those running 2560x1440 3D and larger Resolutions.
- 60z vs. true 120 Hz is yet another debate. And there is not enough time to go over that. However, I see this as a very similar need to the 3D.
- 2560by1600 resolution is 4160 (add the two together) so 5760x1080 is 6840 or 164% of that same resolution. This is why the higher resolutions can be more demanding, far more pixels to process and control. A few run 7680x1440/1600 (or 219% and 223%) and are not yet happy with the overall performance of the GPU's raw power to get the job done even in QUAD SLI 3Gb 580's. So we still have room to grow for those on the edge. And that will never change.
- Let's not forget to mention that with the recent introduction of Adaptive Vsync and the Target Frame Rate you can actually fine tune your cards to fit your entire system needs so that all the Processing power goes to keeping a consistent 60fps target. This is actually beneficial to you more than seeing peaks of 200+ with hard drops down to 30fps...
- No two computer systems are alike. It is best to simply go with what works best for your budget and not worry at this time about 4G or 2G. Nvidia has really hit a grand slam with these 600's... For the perfect balance... Two GTX 670 4G cards are worth more to those demanding systems to do 95% of every game out and will be in the next 18 months, and in 2d 5760x1200 res @ 60Hz and below... Beyond that, it is personal preference/need/want/desire... Everyone "Wants" a Porsche or Lambo, but the majority are quite happy with a Mustang GT, Camero SS or Corvette...
