i would just get the 1x6970. You can also save money there by getting a cheaper motherboard with only 1 pcie 16x slot. Remember if your going for crossfire 6850's not to get a motherboard with a 16x/4x pcie slot setup, you will have problems. Get a 16x/16x or 8x/8x setup.
the x16 and x4 setups dont have as bad of losses as you would think
its not about the losses, its about it not working properly at all sometimes, and more likely to get microstutter as when cards are running different bandwidth slots, its harder for the frames to come out in sync.
Depends on the card, if you put 2 6970 in crossfire then the loss is significant. If you put two 5770 the loss is not that big.
I also recommend the 6970. A single card always means less problems and more stability plus less heat.
+1 ; ive always liked putting one high end card instead of 2 mid ranged cards because of scaling and driver issues, etc. when they work correctly its crazy good, but i like the dependability of one card
I agree...go with the one 6970. I had a problem my first time building where not every game recognized SLI (nvidia obviously) and the game would only utilize one of the cards which was mid-range because I bought 2.
+1 beebahboo...you can always wait for prices to drop and grab another 6970...