That software will only burn at 18x if you have the media capable of 18x. Look at your dvd's and find out. I can't find any at newegg or tigerdirect but that doesn't mean they aren't out somewhere. Are you sure that wasn't a cd you were burning?
no no, it was a DVD, because i buy these from a warehouse, they're NexxTech, and on the DVD it says 8x and it burns at 18x and only the DVD-R, i also tried the dvd+r and they only burn at 8x
Some burners have "overspeed" that allows them to burn to media at a higher speed than they are rated at. Just remember that the ability to burn faster in some cases may not produce a copy that is as good as a slower burn. My Samsung burn 18X on 16X media if I choose maximum speed setting.