I am still running 10.9.5 and after perusing a lot of posts on this site and others, about 10.10.x, I will not be changing any time soon. It appears to me that with my hardware, there is no way to tell if 10.10.x will work properly on my Mac or not. What a shame. What ever happened to those heady days when I bought a Mac so I could have a LOT fewer issues than with a Windows machine - even though the Mac was much more expensive to buy? When having an OS written by the same company as supplied my Mac was much better than Windows? What a shame. It seems now, that all Apple cares about are profits and selling iPhones and iPads. What a shame. If I'm going to have these kinds of issues, I may as well go back to Windows hardware. What a shame.