iMac screen turning on and off at random

[paperbottle]

Would be glad if some of you can give me some ideas as to what to do with my iMac.

I have a 24" 2007 iMac, the first aluminum ones, 4Gb of Ram and a recently upgraded HD to 1Tb (from a 320Gb failed drive).

Recently, I have noticed that under some active usage, such as playing World of Warcraft or Excel, the screen will start to turn completely off for 10 seconds, and then back on for 10 seconds. It will continue to do this for about 3 hours, turning on and off every few seconds or 15 seconds. It will mostly turn completely dark but would also sometimes flicker...

The curious thing, is that if I continue to keep playing, the screen would cease doing this after about 3 hours and then be completely normal and fine.....

but the next night, the symptoms would repeat itself, and would consistently go away after active usage (3 hours or so)

Imagine this, as if the iMac itself needs to be "warmed up" for 3 hours before normal usage..


It would also appear that if i hit the machine (or tap it), this may sometimes bring a dark screen back to life for a few seconds. My dog barking would also affect this turning on and off......

I plan to bring it to support...but I just want to get some ideas from you guys as to what this can possibly be...

Some of my guesses

1) It cannot be software as physically hitting it or my dog barking would affect the rate and speed of the random turn ons and offs..

2) It could be a loose connector from my recent transportation of it while upgrading my HD, but then why would it become normal after 3 hours of usage??

3) Maybe something to do with RAM or video RAM? It is faulty, and thus only prolong heavy usage would "run it in" for the session? After not using it for a while..it goes back to its failed state?

4) God hates me

Would very much appreciate your ideas......it is driving me nuts... imagine working or playing a game....and closing your eyes at random times for random amount of time....

many thanks

 

[Trexznl]

Lol, you're seriously a WoW addict if you keep on playing until your iMac calls it a day because it's weary of telling you to stop playing WoW..

 

[paperbottle]

Lol, you're seriously a WoW addict if you keep on playing until your iMac calls it a day because it's weary of telling you to stop playing WoW..

That's what my wife said...that it is a sign that the iMac is telling me to quit......


....until after 3 hours it goes back to normal and working fine until I stop playing..

So I tell her that the iMac actually NEEDS more WoW to function properly.....

 

[kilowattradio]

Would be glad if some of you can give me some ideas as to what to do with my iMac.

I have a 24" 2007 iMac, the first aluminum ones, 4Gb of Ram and a recently upgraded HD to 1Tb (from a 320Gb failed drive).

Recently, I have noticed that under some active usage, such as playing World of Warcraft or Excel, the screen will start to turn completely off for 10 seconds, and then back on for 10 seconds. It will continue to do this for about 3 hours, turning on and off every few seconds or 15 seconds. It will mostly turn completely dark but would also sometimes flicker...

The curious thing, is that if I continue to keep playing, the screen would cease doing this after about 3 hours and then be completely normal and fine.....

but the next night, the symptoms would repeat itself, and would consistently go away after active usage (3 hours or so)

Imagine this, as if the iMac itself needs to be "warmed up" for 3 hours before normal usage..


It would also appear that if i hit the machine (or tap it), this may sometimes bring a dark screen back to life for a few seconds. My dog barking would also affect this turning on and off......

I plan to bring it to support...but I just want to get some ideas from you guys as to what this can possibly be...

Some of my guesses

1) It cannot be software as physically hitting it or my dog barking would affect the rate and speed of the random turn ons and offs..

2) It could be a loose connector from my recent transportation of it while upgrading my HD, but then why would it become normal after 3 hours of usage??

3) Maybe something to do with RAM or video RAM? It is faulty, and thus only prolong heavy usage would "run it in" for the session? After not using it for a while..it goes back to its failed state?

4) God hates me

Would very much appreciate your ideas......it is driving me nuts... imagine working or playing a game....and closing your eyes at random times for random amount of time....

many thanks

I would first do a hardware test. Put the original install cd/dvd in the drive disconnect everything except the keyboard and mouse and hold down the D key, this maybe different for your iMac, I have a mini so that is the procedure I use, consult your computer manual.
This will tell you if it's a hardware problem and what the error code is. Since you opened the computer and modified it one thing to check is to see if a wire or ribbon cable has come loose. The fact that after 3 hours the computer acts normally tells me most likely heat expansion is occuring so that could be a connector or ribbon cable that was become loosened.

 

[keysersoze]

4) God hates me

LOL that cracked me up haha. I have nothing to add, but thanks for adding that bit of humor

 

[Lukeyboy01]

Video card inverter issue? if it is your doomed cuz its soldered to the motherboard. Hope you got Apple care.........