Yep...exactly my thoughts. Need more than 3GB per GPU.

Knowing Nvidia and GTX 590, 690...they will not give us more than 6GB for 790.

Wait a minute, these double cards work pretty much the same way as SLI? As in the memory pool isn't shared, but rather mirrored? Very lame if true...

Yeah its kind of unfortunate. Someone out there just bought a GTX 690 4GB for $1000 dollars and is about to try to play Bioshock infinite on 3 monitors with cranked MSAA. This is a game with somewhat low GPU usage requirements and GTX 690 can max it out in theory...but BAM, VRAM limit wall hits.

Not so fast Jimmy...Not so fast.

Yep, they do!

Plus, the Double-GPU cards generally have lower clockspeeds and in extreme cases PCI-E contention.

It all essentially boils down to advertising.
Back in the day when 3dfx had a couple of VSA100 chips on a single card, they would advertise them as 64Mb/128Mb etc'.
That is, each GPU on the card had that much memory all to itself, no sharing.

Fast forward to today and AMD and nVidia will advertise a high-end dual-GPU card with 3-6Gb when each GPU actually only gets half of that.
However, there is one exception to that rule, some compute scenarios will use the entire memory pool. :)

It's almost as bad as Hard Drive manufacturers stating 1Gb as 1,000 Megabytes, when in fact it's 1024 Megabytes, so you always get less than the advertised capacity in windows. :P

With my heavily overclocked 7970 I trade blows with a 780.  That makes one of his Titans 15-20% stronger than mine (Plus he has Double the VRAM for ultra-high resolutions).

Now I can play Battlefield 3 100% maxed out at ~100-120 FPS in 1080p (Single player).  So his PC 2.5 times stronger than mine (Or probable 3 times when they are overclocked).  He could play any game maxrd out in 1440p at 60+ FPS (Including Crysis 3 and  Metro: LL).

In other words, there is no game he cannot max out lol!

I agree.  And that is why I will not buy a dual card until they make sense.  The VRAM isn't even the problem though:  They suffer from same scailing and compatibility problems using two cards have.  That makes no sense to me and it should be a harware level forced SLI/Crossfire that scails in every game by at least 80%.

Otherwise I would feel like a beta tester who is out $1000....

While this is still somewhat correct, the driver/scaling issues for these cards are not as big of a problem anymore. Very few games don't have an SLI profile ready even before release and the ones that don't, usually don't need to use SLI.

Last game I played that had scalling issues in SLI was Batman Arkham City, but on a GTX 680/690 it already ran 90+ fps so it was not even necessary.

Even 3 cards make a lot of sense, as long as you have a multimonitor or a 4K setup...the issue with that is VRAM.

Here is a nice breakdown of most current PC games and how many cards are needed to play smoothly and at what resolution.

http://uk.hardware.info/reviews/4632/36/geforce-gtx-700-series-sli-review-geforce-gtx-760770780-in-sli-and-3-way-sli-how-many-cards-do-you-need

I personally would have no issues paying 1200 bucks today and going 3 way SLi with a GTX 770 4GB... I would however have major issues paying 2000 bucks for 3X GTX 780 and having only 3 GB of VRAM.

Oh believe me man I know all about PC hardware lol!  I have built MANY PC's.  But I look at it this way:

-2x680's cost $800

-1x690 cost $1000

-2x680's overclock and thus perform better than a 690

So for $200 extra dollars I better not just be trading a little less power use for extra space.  If they are going to sell it as a single card, it better work as a single card.  Until that happens  (And they are VERY close), there will always be a better solution...

Why wouldn't you consider Captain_Toms suggestion and get 2X 780? Should be the same thing but you will get better overclocks and probably pay less. i really doubt that the 790 will be $1000 bucks...$1200-1300 minimum.

Or 3x Geforce 780's. :)
I'm pretty sure, CGI does have an Asus Sabertooth x79 with 2x PCI-E x16 slots and an x8 slot like myself.