I am building a new system. I am starting off with two 5770 in crossfire. That's pretty straightforward. But I would like to keep the option to ad a third or fourth down the line. But I have been reading in some reviews for 5770s on Newegg that some only have one Crossfire port on them, and therefore can only be connected to one other board, so adding a third later is out of the question. This is the card I am looking at because it's a good price right now, but I don't want to get it if it's going to hinder my upgrade path later.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814161317&cm_re=5770-_-14-161-317-_-Product
http://www.newegg.com/Product/Product.aspx?Item=N82E16814161317&cm_re=5770-_-14-161-317-_-Product