This is how the thread should have started. Changing from CrossFire HD5850 to HD7970 might result in a small performance boost, but it is worth in every way and recommended.
Changing from CrossFire HD6970 to HD7970 is pure imbecility
. The power savings and whatever BS new technologies incorporated in HD7970 do not justify the loss of performance by a huge 50 % amount.
It does not take a genius to figure out that 3000 shaders clocked at 880 MHz are better than 2000 shaders clocked at 925 MHz, as well as memory bandwidth of 352 GB/s is better than 264 GB/s. I am thinking that people voting for HD7970 are just ordinary fools, who have no life and post in forums for no reason, and they do damage to the forums with their insignificant votes without any reasonable arguments.