ATI's upcoming RD600 chipset for the Intel Conroe processor will feature three PCI Express x16 ports:
As you might know, ATI wants to do a lot with what the chip firms now call physics. Most especially it wants to get you buying three graphics cards for your PC.
Two cards for graphics will cost you and a third one for physics might not be super expensive but it won't be cheap either. Of course, it all depends on what you want, as the top ATI physics chippery comes with the top ATI graphic card.