Please be aware,if you attempt to complete the free upgrade/update from Mountain Lion to the new Mavericks you may render your system un-bootable. We are not recommending the update/upgrade as it is not a security based update and reviews have been reporting Slowness, Bugs, and Other Problems. (Speed Decrease among them*) Please contact us if you have concerns. Regards, COEHD IT Team http://It.coehd.utsa.edu