I am building a new gaming computer. I have been reading lots of reviews and checking prices for a few weeks. What i have been told so far is to ether get 2 gtx 560 ti or get 1 gtx 680. buying 2 gtx 560ti will cost me only $300 and a 680 will be around $460.00. The game i will be playing most is call of duty black ops 2.
I would not do a lower end sli configuration. I would go for a single 670 or a 680. SLI configurations will make a lot more heat, and you may need to upgrade your power supply to handle 2 hungry cards. Going for a single and more powerful card would also offer you expandability in the future.