For the past week, my late 2009 27" iMac (3TB HDD) has been acting up. I leave my computer on all the time, but when i go to use it, it just has a grey screen, so I reboot, everything seems to start up fine (slowly), but when I go to launch any application, i get the spinning beach ball, then after a while the screen goes grey. Also, sometimes during the reboot, the screen will just turn grey as well. Any ideas??? (I am running Yosemite and have Not upgraded to El Capitan yet)
Thanks in advance
Thanks in advance