GTX 680's or 690's

waiting for 700 is like waiting for your death to come   and as for me the 690 is a serious overkill for any pc i would suggest keeping some of your money and spend other on a good 680

What is your monitor resolution?

Asus DCII TOP(if you can find one) or MSi Lightning version.

At 1920 x 1200.....two of these beat both the 680's and the 690. yes, you can get an OC'd 680 too but the cost per frame is significantly higher.

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

http://www.techpowerup.com/reviews/ASUS/GeForce_GTX_670...

Guru3D uses the following games in their test suite: Hard Reset, COD-MW2, Far Cry 2, ANNO 1404, Metro 2033, ANNO 2070, BFBC2, BF3, Crysis 2, AvP, Lost Planet 2. Total fps (summing fps in each game @ 1920 x 1200) are tabulated below along with their cost in dollars per frame @ 1920 x 1200:

660 PE gets 851 fps for $300 at a cost of $0.35 per frame
670 DCII gets 999 fps for $420 at a cost of $0.42 per frame
670 gets 917 fps for $400 at a cost of $0.44 per frame
680 DCII gets 1077 fps for $520 at a cost of $0.48 per frame
680 gets 989 fps for $500 at a cost of $0.51 per frame

For bigger resolutions on single monitor, I tend to lean to AMD cards .... on multi moniutors, look at some of the graphs here:

http://uk.hardware.info/reviews/3026/nvidia-geforce-gtx...

Not necessarily that particular article but that's one of the latest ones so has the most current data.

What sort of performance are you after. Upgrading these levels of GPUs every generation is not cost effective. You could get away with a 670 now, then sell it when the 780/785/790 come out and commit to that. Alternately, just get the 680sli and be set for the next few years. Hope this helps