IMAC Yosemite restart without notice
IMAC RETINA 5K 27-inch late 2014, OSX Yosemite 10.10.4
4 GHz Intel Core i7
16 Go 1600 MHz DDR3
DGKP210PFY14
AMD Radeon R9 M290X 2048 Mo
Restart sveral time without notice
iMac (27-inch, Late 2013), OS X Mavericks (10.9.1)