So there were two "dvi" cables in the box with the MacPro. One is the DVI-VGA cable that's mentioned in the manual. The other appears to be a DVI-DVI cable, and I can't figure out what it's for or what it does. It's male-female, so essentially a 5" extension, which would seem silly. So I'm guessing it .. does something, in those 5 inches, but I don't know what. The two cables were in little plastic bags, with two different model-type numbers: 603-8525 and 603-8471, but I can't find either of them on the web anywhere.