My iMac was working normally when it suddenly flashed to a solid blue screen. I restarted and it came up with the loading screen as normal burt with vertical pink lines. It gets about one third of the way through the start up sequence then just goes to a grey screen and hangs. Tried Safe boot same thing. Ran Apple Diagnostics short and long tests and comes up with no issues.
Occasionalyl iMac does start and works for a while then crashes to an unresponsive grey screen.
Any thoughts on what the problem would be?
6 months out of AppleCare too!!!
