I personally have yet to see a Mac Pro that could have potentially been upgraded as a CTO as they all only seem to have processor differences and the base amount of RAM. All have 1 Superdrive (I feel sure some would be equipped with two), a 5770 graphics card (have yet to see a 5870), and no additional RAM or disks, or even an SSD. Does Apple strip these down to the base configuration every time when they are recertified sans processor(s)?