imac 27" black screen

Question

Level 1

9 points

imac 27" black screen

Imac was purchased about 4 years ago and updated to Yosemite 6 months ago. for the past 2 months i have been experiencing the screen going black. it most of the time corrects itself and just seems to be flashing. Its not regular, there is no pattern and twice it just went black and didnt return until i switched everything off and restarted.

my second screen, A Benq, shows its fine when this happens - i can see all on the second screen and i can see all external hard drives are connected, working and accessible.

i have googled and checked previous discussions but i still dont know what course to take? all /any advice greatly appreciated.

thanks

iMac, Mac OS X (10.7.5)

Posted on Oct 19, 2015 5:51 PM

Reply

Answer 1

fynearts Author

Level 1

9 points

Nov 1, 2015 3:02 PM in response to fynearts

hello???? anyone ?

Reply

Answer 2

Eric Root

Level 10

685,293 points

Nov 2, 2015 12:37 PM in response to fynearts

What happens if you disconnect the 2nd screen?

Reply

Answer 3

fynearts Author

Level 1

9 points

Nov 2, 2015 2:21 PM in response to Eric Root

why do you think it might be the second screen? the two screens have been together for 2 years with no problem ... this blackout thing is intermittent and only started a couple of months ago. .. curious as to why you consider it might be the culprit - from all the reading i have been doing for ages now everyone was talking about it being other possiblities - all of which dont really seem to pinpoint a real solution or even what the actual problem is.

i havent disconnected 2nd screen but will try it . thanks for the reply/suggestion.

Reply

Answer 4

Eric Root

Level 10

685,293 points

Nov 3, 2015 12:47 PM in response to fynearts

You are welcome. I don't know if it is the second screen, but disconnecting added items often clears a problem, so it was something to test.

Reply

Answer 5

fynearts Author

Level 1

9 points

Nov 3, 2015 3:17 PM in response to Eric Root

ok i have done that ... all good for a day now but the black screen was intermittent ... will TRY to keep second screen disconnected for as long as possible. If it is the screen how do i make sure it doesnt do it? perfectly good screen ....w orked together for a long time now and this thing is sudden - would you hazard a guess as to what is causing it? will keep posted ... thanks again

Reply

Answer 6

kgiannis

Level 1

8 points

Jun 8, 2016 8:17 AM in response to fynearts

I have a problem about 3 days ago.

When i open my imac with button, i listen the mac start up sound (https://www.youtube.com/watch?v=XZ1mpI01evk) with Black monitor and the mac start up sound repeat again and again with black monitor.....Nothing more 😟

I try to disconect the imac and connect again, press cmd+R or cmd+R+T but nothing.

I call the Apple support center in Greece and they dont know nothing and dont help me.

Does anyone the same problem ??

Reply

Answer 7

Nov 15, 2017 12:04 PM in response to fynearts

Apple iMac 27” i7 2011 3.4 Ghz

Only 3 led lights will come on!

I put in new power supply!

I put in new backlight board!

I bought another monitor!

I got new 3 new ribbons.

Computer starts with external monitor works fine.

I while ago I put in monitor ribbon that has a pin missing it went black after a few minutes.

Since then the screen will not light up.

I tried everything I can think of…

Have you ever run into this or heard of this problem.

So I’m thinking it the old ribbon did something to the motherboard.

I took out motherboard it looks good no bulging capacitors or leaks but i did notice a little white residue on front of motherboard under 2 capacitors.

very little.

Howard

hmaher777@gmail.com

Reply