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iMac Graphics Problem
- Thread starter Love
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I don't know why you keep insisting he's got software issues. He's got artifacting that is getting steadily worse. That was EXACTLY the pattern of events that I experienced with my prior 20" Core Duo iMac that ended up needing a logic board replacement.
I'm glad to see he's finally calling Apple. That is going to settle the matter one way or the other. Send it in and let them sort it out.
I did some quick research and found screenshots of identical graphics problems in iMacs.
The consensus is that the problem seems heat-related, possibly due to a fan control malfunction. (fans not throttling properly or something to that effect)
There's some scuttlebutt regarding Leopard installations causing errors in the SMC.
Have you tried restting the PRAM and SMC?
The consensus is that the problem seems heat-related, possibly due to a fan control malfunction. (fans not throttling properly or something to that effect)
There's some scuttlebutt regarding Leopard installations causing errors in the SMC.
Have you tried restting the PRAM and SMC?
Reset PRAM: Hold down Command-Option-P-R during startup until you hear the ROM sound twice.
Reset SMC: shutdown the machine and unplug all cables for at least 15 seconds; plug in the power cable, followed by the mouse and keyboard, then press the power button to start up the machine.
GLReset SMC: shutdown the machine and unplug all cables for at least 15 seconds; plug in the power cable, followed by the mouse and keyboard, then press the power button to start up the machine.
It just happened to me also while playing a movie under Movist.
Did a hardware (not extended) check and all came fine.
Now is working alright but got me worried
It's almost 1 month old 20' iMac (with 800 FSB)
Love, did u work out the issue?
Did a hardware (not extended) check and all came fine.
Now is working alright but got me worried
It's almost 1 month old 20' iMac (with 800 FSB)
Love, did u work out the issue?
I certainly appreciate you guy's concerns! I took it to my authorized service provider (no apple stores here ). They replaced the motherboard, and he said if it makes the graphics screwup again, they'll replace the LCD.
). They replaced the motherboard, and he said if it makes the graphics screwup again, they'll replace the LCD.I have had this problem lately as well. Is there a chance that this is caused by a lack of fan speed? There is no easy way to get in and clean the fan on an imac, and given that I smoke by it all the time, I know it gets pretty dirty inside. Any thoughts?
I would be VERY wary of blowing compressed air into a computer. If you should so much as tilt the can slightly in the wrong direction you run a risk of shooting a stream of liquid propellant into your Mac. This is not a scenario you want to occur.
It's not nearly as effective but I recommend vacuuming the vents both top and bottom. Aside from that and disassembling the case (also not easy) there's not much you can do.
The graphics driver (specifically, demanding graphics instructions) is causing your GPU to overheat.
Maybe a faulty heatsink installation issue, or an issue with the GPU firmware causing the core/memory clocks to run at the wrong frequencies.
(iMac GPU probably runs at lower than factory-spec frequencies, to mitigate overheating problems in the cramped aluminum enclosure.)
Maybe a faulty heatsink installation issue, or an issue with the GPU firmware causing the core/memory clocks to run at the wrong frequencies.
(iMac GPU probably runs at lower than factory-spec frequencies, to mitigate overheating problems in the cramped aluminum enclosure.)
If you read to the top of this thread I suggested that the OP might have had a hardware failure (specifically a bad GPU or logic board) since those symptoms are exactly what I experienced about a year ago on my 20" Core Duo iMac. I was able to boot in safe mode and strangely, had no problems running Windows whatsoever in Boot Camp. But in OS X it was artifact city and eventually the machine just locked up period.
Well the way you put it it seams like a OS driver bug that will eventually cause a hardware malfunction. Do you know if there is any update/patch/driver that corrects that?
In my case the colours get all fuzy in a light blue pathern (sort of) but from the first moment i start the pc! I don't need to start any program. It just boots like that. Then if I shut it down or send it to sleep, when it starts or awakes its all ok again. It already happened to me twice. I bought my iMac 20'' in July 2008.
Did two changes to the standard config:
4GB RAM
750 GB Hard Drive.
(Just to clarify: I didn't do it myself, i just ordered it from the AppleStore with those changes
)new 24" iMac screen issues on startup
I have a new iMac 24" desktop that was purchased in July. About 2 weeks ago when I start my computer (either when i have logged out or from a complete shut down) the screen comes up and looks like a bunch of hyroglyphic (sp) black and white lines. It remind me of a bad tv picture with details.
Can anyone help with this???
I have a new iMac 24" desktop that was purchased in July. About 2 weeks ago when I start my computer (either when i have logged out or from a complete shut down) the screen comes up and looks like a bunch of hyroglyphic (sp) black and white lines. It remind me of a bad tv picture with details.
Can anyone help with this???
To the users having these problems:
Your graphics cards are faulty and need replacing. My 20 inch iMac with Radeon X1600 is also displays artifacts, in both OS X and Windows and Boot Camp. Best send it back to Apple before your warranty runs out.
It is not a software or driver issue. It won't fix itself.
If you have Windows installed in Boot Camp, see if you can see the same problem there. That will prove beyond doubt a hardware malfunction, and will probably hurry along Apple's tech support (i.e. they won't waste time searching for anything in OS X.)
Your graphics cards are faulty and need replacing. My 20 inch iMac with Radeon X1600 is also displays artifacts, in both OS X and Windows and Boot Camp. Best send it back to Apple before your warranty runs out.
It is not a software or driver issue. It won't fix itself.
If you have Windows installed in Boot Camp, see if you can see the same problem there. That will prove beyond doubt a hardware malfunction, and will probably hurry along Apple's tech support (i.e. they won't waste time searching for anything in OS X.)
Actually, even though I was one of those on this thread from the beginning saying that software issues probably had nothing to do with the OP's problems I did hear of an issue recently with nVidia-based iMacs so I would double check to see if there are any firmware updates you're missing. That said, that surely DOES look like the artifacting of a bad logic board/GPU.
Not necessarily the case. On my 20" Core Duo white iMac (Radeon x1600) with the bad logic board even after OS X failed to even boot up anymore I was able to boot into Boot Camp and Vista ran smooth as silk, even in 3D games/apps. I'm not entirely sure why.
When I sent it back to Apple for service they confirmed the fried logic board immediately and it set me back $500. It was 6 weeks out warranty as I may have mentioned above (this thread is so old). Anyway, I am only halfway through the 3 years of Applecare on my current iMac. Never again....
A specific graphics card problem should show up in each OS. It's possible that there is some other kind of logic board malfunction, though.
I don't think that's quite right. The top left of the case can become so hot it hurts your fingers with no ill effects.
The heat may be a red herring. A faulty GPU will give you all the symptoms you're describing.
I'd be pushing for a whole new machine, not a logic board replacement.
The heat may be a red herring. A faulty GPU will give you all the symptoms you're describing.
I'd be pushing for a whole new machine, not a logic board replacement.
Sorry for resurrecting this thread, but I'm experiencing a weird graphics bug on a 24" iMac. On the desktop and in other applications there will be these square boxes made up of 4 green lines. This pattern repeats on the very top of the screen. Interesting thing is that this iMac is connected to a projector and if the displays are set to mirror they both have the green boxes. If they are not set to mirror then only the built-in display on the iMac shows the green boxes, the image from the projector is fine. iMac is fully up to date with all software updates and I tried installing the graphics driver again from Apple but it said it would not install because it was already installed. Attached is a screenshot, any help is appreciated.
