If I do a restart of hard shut down, I have to reboot from MAC APPS via the internet. My machine is an early 2008 with 2.8GHz quad core. 10 GB of memory and 3 hard drives - the original, one with 1TB and one with 2 TB (partitioned as two drives) Started with the 10.5 OS, then upgraded to 10.6 Had a major crash in December and had things restored at a MAC service center. In mid-February, OS started to again crash. Fortunately had all important files on the other drives, so I reinstalled 10.5 then upgraded to the 10.6 and then eventually the 10.10.2 Since then, the 10.10 has crashed so often that I do not shut down the unit; just let it sleep. If this subject has been discussed, please excuse me - new to this site. Also, please do not get too technical should you reply. Old fart that I somewhat technical savvy. Thanks, FB