As a general rule the boards rise in spec as the numbers rise. ie UD3, UD4, UD5, UD7 etc obviously there are some variations to this but in most cases it works. The GA-Z68X-UD7 is a top of the range board and will have more ports, slots etc than most of the others. That is not to say that it will have everything though so do make sure that you read the spec list before purchase.