Crysis has some problems with Crossfire and SLI setups with newer cards.
But to answer your question, yes it will.But more so in CPU intensive games such as BF3, Crysis 2,etc.Crossfire scaling is near 90% with the 68xx series so you can already see that if your only getting a 40% improvement in Dirt 2 that they are being bottlenecked.
the problem with intel is that crossfire motherboards are f-ing expensive compared to AMD's for some reason... and the 2500k isn't cheap either...
But I guess that's the only solution to my problems with crossfire. I will have to save a lot of money to buy a 2500k plus a crossfire mobo for that processor.
There are certain games, like farcry and Shogun2 where I get 90% of improvement....
Instead of getting a i5 you can get the FX 8120 and it will be pretty awesome improvement when compared to the i5 because in a real world use, u run a IM messenger, browser, aother programs and the game all together and the FX8120 will give you a consistent frame rate compared to the i5 because the quad core of the i5 will get bottle necked.
If your mother board supports it i think you can get a FX6100 or a x6 and it will cost way less than getting a new mobo + a new processor for an i5.
I picked up my Z68 board as an open box for $80 on Ebay.It usually retails for around $180.You'd be surprised what good deals you can find on there.Although I would suggest not buying a processor from there.
But yea I know what you mean.Believe me I was really happy with my 990FXA board but the old gen AMD CPU's just can't hack it anymore.And the fact that you have to O.C. a FX CPU in order to not bottleneck a crossfire setup just really turned me away from it.Intel is expensive but the performance increase is well worth the money.