2007 iMac - video dims to black then comes back

[GilesM]

Hello

I have an iMac from which is connected to an external monitor so I have two screens.
Just recently I notice that just once or twice a day both screens would fade to almost black then the image comes back again. The whole process takes around .5 of a second.
I shut the machine down yesterday and the issue persists even though it is very infrequent.

Is a fault about to develop? Any ideas?

 

[macuser154]

Are you on 10.5.7? I have been having this problem (not as frequently as you) after I installed 10.5.7.

 

[GilesM]

Hello,

yes indeed I am running 10.5.7 and as far as I recall this has only started some time after installing 10.5.7.
I will be quite relieved if this is software related.
Having said that my wife also has an iMac (2008 model) also running 10.5.7
and this issue does not seem to happen, but she uses it perhaps 10% of the time I use mine.

I hope this is software related as that may be easier to fix!

 

[macuser154]

Hello,

yes indeed I am running 10.5.7 and as far as I recall this has only started some time after installing 10.5.7.
I will be quite relieved if this is software related.
Having said that my wife also has an iMac (2008 model) also running 10.5.7
and this issue does not seem to happen, but she uses it perhaps 10% of the time I use mine.

I hope this is software related as that may be easier to fix!

Some of the bugs in 10.5.7 don't affect all Macs, so I wouldn't worry about your wife's Mac. Apple is working on 10.5.8, hopefully that will fix the problem.

 

[GilesM]

Well, I do hope so, I don't mind waiting for a software fix too much as long as it's not a hardware fault.
Anyway, let's hope for the best!

 

[macuser154]

I just thought I'd mention that I downloaded and installed the 10.5.7 combo update, and that seems to have fixed the problem for me if you want to give that a go.

 

[GilesM]

so, does that mean that I should install the Combo update even though I have done the regular updates? Interesting I will give it a try.

Thanks

 

[GilesM]

Well, I installed the combo update this morning and it has not happened since, but I have hardly been 10 minutes on the machine all day.
I will have to wait and see.

Hopefully this will fix it.

regards

 

[GilesM]

OK, this just happened again, but it's a little different, it no longer dims to black, but now everything on the screen except the wallpaper vanishes for a moment and then comes back.
Very strange any ideas? anyone?

 

[007bond]

hmm maybe finder is crashing. im no terminal expert, but i think that u can find out why finder crashes in terminal right? command line people help this person

 

[GilesM]

Im am not sure if I went about this the right way, but I had this happen at 06:16:52 this morning. So I went to the Console a tried to see if there were any reports in the "All messages" file for that time and date, and there is nothing there, nothing even close in terms of time of the event and nothing that looks like a crash report.

 

[007bond]

Im am not sure if I went about this the right way, but I had this happen at 06:16:52 this morning. So I went to the Console a tried to see if there were any reports in the "All messages" file for that time and date, and there is nothing there, nothing even close in terms of time of the event and nothing that looks like a crash report.

thats odd. i think u should try going to an apple store if u have apple care

 

[GilesM]

hello,

well I do have Apple Care but am no where near an Apple store, I think I will try the phone support first.
Another thing I might try is removing my 2nd monitor for a while see if that makes any difference.
This has only happened recently since the addition of a second monitor, but that could be just coincidence.

 

[GilesM]

Well, it may have been a connection problem. The other day my screen started to display more symptoms, the display became distorted with lines of break up and drop out. So I shut it all down and disconnected the Apple cable connecting the second display.
Now all seems OK, even the original issue has not surfaced again.

Perhaps this is the answer, but I will keep watching...

 

[Saternoc]

iMac Screen

Recently my aunt's iMac screen went completely black. She took it to the apple store and they told her that it would cost her about $700.00. I started doing browsing around and found that iMac's esp. the 24 inch screens are susceptible to getting spots or lines running through their screens.
I was wondering if you knew if Apple took of this issue because I am considering purchasing a "desktop" Mac. Would I just be better off with a mac mini and a separate screen? I don't do professional photo editing or heavy gaming incase you were wondering. However I do like that the iMac has better graphics, a stronger processor, and more hard drive space.

 

[GilesM]

Well, my particular issue seems to have been resolved by reconnecting the screen. I am sure that such things would indeed be covered by Applecare should you choose to buy it and by the standard warranty for the first year.

You should by the machine that best suits your needs. These forums can give a somewhat distorted view of the product because no one posts to a forum when all is going well but only when they have a problem. So it makes it seem as if the product is more problematic than is actually the case.