if you have a Classified I wouldn't step up unless it was for a 6gb Ti, 6gb Classy, or 6gb reference.
 
The classifieds are pretty awesome and can be overvolted significantly.  The details are explained in this thread from OCN, some very helpful people can explain it better than I can!  
 
http://www.overclock.net/...x-780-owners-club/0_50
 
 

beekermartin
That thread is 1800 pages long! 
 
I think the general consensus is the 3gb Classified is a great card and to go down to a stock based card with 6gb doesn't make any sense.  

Well i WOULD agree with you.. until last weekend.
 
why?
 
here's why:
 

 

 
AND...
 

 
 
as you can see BioShock infinite on ultra eats clearly more then 2GB of Vram..  the game started to LAG... severely..
 
the funny thing is.. the frames were VERY decent above 40 so i did not understood whats wass going on until i saw the mem values that were being used..
 
and trust me .. this game seemed thirsty for Vram... witch i am sure 3GB would suffice BUT...
 
go for this sucker advice WHO should have bought the 4GBb version of the 760.. and buy yourself at least a 4GB version (if there is any) for the next years...
 
 
cheers!

beekermartin
If I was buying a new card today I would go with the 6gb version.  But to go from a 3gb Classified to a 6gb 780 SC it is going to cost me @$80!  If I could go from the 3gb Classified to the 6gb Classified for @$80 I would probably do it.  

mate ... all i know is this:
 
i should have bought the 4GB version.
 
thats all i can tell you. :) i should have spend those extra 60€...  how i regret not doing it so..

star cit hangar module eats up all 3 gigs of my 780 sc but its not optimize yet im running 1920x1200 and all maxed 

Vlada011
Miguell, you regret because you bought 2GB version.
Why, what's happen now in games, do you notice some problems because less video memory.
You are really limited with 2GB? They could go only with 4GB version(GTX760/GTX770). 2GB for low end cards.
They always give more than enough memory. Why now people with mid range models to feel limitations because lack of video memory.

yes i did noticed problems.
 
like i said in the #4 post the game started to lag..  lag is the best term i can find to describe what was going on.. 
 
i though it was lack of frames or something but the frames were fine! but it was the game just stopped responding = unplayable! weird symptom i never experienced.
when i realized what was going on i noticed that.. IT was not lack of FPS but lack of Vram causing the game to behave like that.
 
i am not saying i am totally limited! this 760 Chip is awesome and im not even fully enjoying it to the full due to my CPU!
 
but from what i see from some PAST games, from a few CURRENT games.. and some FUTURE games ahead.. i now regret not acquiring the 4GB version.
why do i regret? cause this will sure happen again in a Vram hungry game specially with ultra settings..in some near future.
 
my brother defends we should SLI but he thinks SLI is a 100% perfect performance and mem sum of 2 gfx cards witch is not true unfortunately.
the performance is fine. i am now feeling limited on the memory part. i did not realize that games were on such level that 2GB VRam is already a minimum requirement on some applications.
 
 

4gb 760/770 does not perform any better than 2gb, there is no performance difference

That cant be a Vram issue then as the benches above ran fine and at even higher resolutions