I did some research on the internet and I contacted Asus to know what was going on. So I learned that the PCB are the new revision.
I wanted to know if the old revision was better... and they are mostly the same, both overheat in crossfire configuration.
I learned that the coolers are really bad for multiple cards setup. These cards should be avoided for any crossfire setup... without any additional cooling solution.
Still, for any single card system, they are easily the most silent and cool 4850 cards.
I am quite lucky to be able to run them in Crossfire at stable temperatures, but adding a 120mm fan really did the difference.
Phhh... stuff like that never occurred when NVIDIA and ATI were selling their cards... now it is more a mainstream reality.
Here the article... interesting read. I usually don't buy anything without reading reviews, but I was trusting Asus and they really let me down this time. Well, I guess it was my last experience with them since I don't plan buying any of their future products.
http://techreport.com/articles.x/16229/4