No problem at all happily it does everything perfectly showing a capacity of 4tb and it happily handles the hourly backups from my system and one month of incremental backups the 2tb predecessor didnt have enough space to backup the system as well as my data

This drive replaced a dead 2tb drive in my mark 1 macpro 8 core running osx 10

7 lion which as the target drive for time machine backups and knowing that in earlier operating systems the mac was not able to access more than 2 tb regardless of disk capacity i was slightly nervous that the total available disk space might not be usable