IMac Screen goes Black

Been there, done this. In my case, it was the power supply. There are (I'm told) two cables inside the power supply unit and one of them powers the screen. Apple replaced the power supply and my black screen problem stopped. (I got a white screen instead and they replaced my iMac after that, but hey that's a whole other story.)

Finally gave up. Sent the Imac back to Apple back to distributor under warranty. They replaced the screen. All is better now. No explanation as to why.

Ok i am trying to stay calm....but when you are in the middle of a high stakes on-line poker game and suddenly you have to sit out for 20 minutes while you beg with your imac to show you some kind of picture whilst you hear the game continuing in the darkness and the sound of your chips being rifled by the other players who no doubt have cheap PC's and are obviously delighted with the fact that you bought an imac..........aaagh

I can't even get through a game of golf on WGT without being blanked out of it. To make matters worse i recently sold my macbook laptop because i switched to ipad for "away from home" projects so i didn't think i would need it any more! How wrong was i? I paid just under £2000 15 months ago for a machine that is now a glorified ipad because i can't do the things i want to do on it when i want to do them.

Maybe, whilst i work out what the problem is, which may take months of experimenting, i can connect another monitor to it and then at least i can see what is happening.

I haven't contacted Apple Store yet but i am not confident that they will be helpful or am i am just being overly pessimistic?

Try contacting Apple and have faith that they will try to fix it. If it doesn't work, call your local consumer protection government body. Regardless of product warranty, a product has to be fit for purpose and your iMac obviously isn't. Its definitely a screen problem (having experienced this myself). They need to fix it for you or replace your iMac if it can't be fixed. In Australia, they will send a technician out 3 times and if that doesn't fix the problem, they will replace the computer altogether.

my screen hibernates/sleeps the same way....started month ago after a macmedia tech company cleaned the dust from under my screen.....ingstarted happen intermittenly....multiple times an hour....a day a week....or nothing for weeks....no rhyme or reason....did the SMC thing (glorified reboot) stll nothing....top of mac 'seems' hot...fan 'seems' loud....but no comparison....mine is a 24" imac....late 2009 build.....never ever had a problem...easy to get screen back on...nothing lost....just move trackpad and comes back.....sometimes jumps back.....not always a smooth transition.....

...right now the top of imac is barely warm.....past couple days been very very warm.....

...any more ideas anyone?!....

...like my toys to be NASA perfect...this drives me crazy...

i think your problem although just as annoying is different from the original subject.Sounds like your computer has some sort of sleep apnoea problem whereas in my case and in the case of the other contributors the screen goes black but the program continues to run so the computer is not asleep as such it is still very much awake but with it's eyes firmly shut....