Display black out

[Royghost]

Hi good day,
Any one come across iMac 27in mid 2011 unit, when start it run ok, but suddenly it go black out, but unit still running in black, when press the power button display come back, awhile it black out again and it keep repeat black out.......

 

[maflynn]

Sounds like some sort of hardware failure, like the GPU

I'd give apple a call and/or take it in to them for diagnostics/repair