IMac Screen freezing strage artifacts and generally just flipping out

[SimSim02]

Hi, I'm new to the forums and am hoping someone can help me out. I admit I haven't read all the archives so if a similar thread has been started already please direct me towards that one.

My Imac is about 2 years old and now the screen keeps freezing with strange boxes, lines or other artifacts. The screen becomes unresponsive although I can still move my mouse and the only solution is a hard shut down. I took it into apple and they suggested my graphic card may be the culprit so I replaced that along with the logic board.

A week later the issue has come up again. I took it back to apple and they have sent some videos I took of the problems to the developers for further analysis. There seems to be no rhyme or reason to it , I can be surfing the net, playing world of warcraft or just simply listening to music and the screen will suddenly freeze up.

The only thing I can think of is that the problem seem to start around the time I updated the computer to Mac OSx 10.6.3. Since then I have updated to 10.6.4 to see if the problem would go away but so far no luck.

I'm waiting patiently to hear back from apple but I was wondering if anyone here had experienced the same thing or at least have some theories about what could be going on with my poor mac

Thank you for any help or insight you guys may be able to provide

 

[AppleZwei]

I bet the video card is failing. Mine has failed 3 times in the last 45 days. Has had to be replaced every time. 24" 2008 iMac.

 

[SimSim02]

HI and thanks for the response. The graphic card has been replaced and it has only been a week. The graphic card couldn't have failed in a week could it?

 

[SimSim02]

Update

Now upon start up I'm getting this scary grey screen with a cryptic message telling me to restart the computer. I restart but I keep getting the same message upon start up. Please if anyone has any ideas about what is going on I would so appreciate some help. It has been a week since I have talked to Apple but still no response.

Also are there cases where apple will completely replace a computer maybe I got a lemon? Any help at all would be greatly appreciated thank you.

 

[Ecoh]

Have you tried re-installing the OS from the installation disk.

I was having some problems after updating to 10.6.4. I called Apple support, the tech told me to re-install the OS because some files probably got corrupted during the install.

I did the install from the original disk , than ran the software update to bring it up to 10.6.4 and everything runs fine now.

 

[SimSim02]

Thanks for the reply. I have done the reinstall twice before the computer kept telling me to reboot.

I took another trip back down to the apple store only to find out that the apple developers DID get back to the store 3 days ago but the store forgot to call me >.<

They said the first problem was a failed graphics card but now a second problem has surfaced. They believe that the cable connecting the power cord to the logic board is faulty or whatever the cord fits into is faulty. At least thats what i could decipher from our conversation as most of it went over my head.

So the imac is currently back at the store they are going to run some more test on it. They have decided to go head and order all the replacement parts they can think of just in case I should be getting it back on saturday if all goes well. All I can say is thank God I got AppleCare

Will give an update on saturday.