2011 core i7 27" screen flicker at low brightness

since my Device is only a few days old. Apple replaces it with a new Unit. A Carrier picks the old one up and delivers a new one asap. They startet the deliveryprocess right now. Probably i can hold my old one till the new one will arrive...

I have the same issue. I hope this is a software issue that will be fixed soon.

I have the issue with my 27 inch imac i5 and bought it at 15 july. now my question is, should i wait for an update or should i give it to the support? I called apple and the guy said there are actually no informations about flickering-issues.

In my Case replacing the Device was the Solution.

Hello all,

I bought the 2.7ghz intel core i5 27" iMac on 9th August 2011.

I noticed my screen flickering this morning and started to search if the problem was common.

I have auto adjust on. I havent really tried making any screen adjustments yet.

I bought this computer because my G5 PPC I had for 8 years just bit the dust!

8 years and not one single problem!

I guess it had to happen one day.

I don't want to return my computer. I've just spent the last few weeks installing and setting it up.

Technology ***** sometimes hey!

I'm going to sit in the corner for a while....

What's the solution, wait for Apple update or return the machine?

I just turned off the 'auto adjust brightness as ambient light changes'. I also have the screen saver set for three mins. I will see what happens.

:/

For me replacing the device was also the solution, if you have a backup of everything you have on your Mac you will be fine away just reinstall your mac from the backup, if you don't, you should! 😉

Hi,

Thanks for the reply killhippie.

I am eligable for return until 29th Aug. I just tried to go through the process of getting this machine replaced. They said reinstall the OS and if the problem persists then I can return the product and and they will fix it!

I said I want it replaced or a rufund.

Looks like you could get it replaced far easier than me!

I'm gutted with this sale.

😟

I think I have finally resolved this issue on my imac 27". I had installed a program recently that included "cuda" as part of the overall program package. As time went on I began to notice a flickering screen. Dimmer brightness. Some yellowing. I was driving me nuts. I cleared the PRAM and it didn't fix the issue. Apple replaced the lcd backlight. Still the screen flickered. I wasn't sure initially that the program caused the problem so I uninstalled the program but still it flickered. But then I remembered seeing "cuda" in the start menu. Cuda is a program designed to work with nvida graphics chips not amd or ati. I removed "cuda" from the start menu. Cleared the PRAM and ran onyx to clean up my system. So far full brightness and color are restored and no flickers. Hope this helps someone else.

Hello,

Just for the record, I spent the weekend doing what Apple support suggested and reinstalled the OS.

I used the disk that came with the iMac. I erased the drive in disc utility and reinstalled the OS fresh.

10.6.7 it flickers

updated via Apple update

10.6.8 it flickers

10.7.1 it still flickers

As it does with any time machine backup.

There was no software on the iMac and it still flickers within minutes of a clean installation.

This has confirmed that it isn't an OS problem problem for me and I will inform Apple Care when they call me today.

I don't want a replacement and I certainly don't want it fixed when it should be mint condition working perfectly.

If it happens now, what's going to happen 2-3 years from now?

I wan't a refund so I can get a tower or a mac mini. Should be nice with a Bravia!

Cheers

:/

Well, I just returned mine right after I posted. The new one works perfectly even after the upgrade to Lion.

i7 iMac 27" same exact problem. On line support said to take to the store, did not offer any other help, said they didn't know what I was talking about!

Initially Apple said "there have been no reports of this problem yet", they did say there was a problem on 2009 models. This was a widely known problem.

It seems from what I have read it's just the luck of the draw. You might get one and it works perfectly. You might get one that has a problem from day one.

No doubt, it is a lovely machine and I'm a bit gutted it didn't work out for me. Apple agreed that this was a machine defect. My unit is being picked up this morning and I will be fully refunded. 🙂

I have just bought the 2.7Ghz i7 mac mini at a fraction of the price and am after the new 30" Sony Bravia.

I still want to know why is happening in the first place?!

Glauconite, we had to be quite insistant, we did not want it fixed (why should we) and we only wanted a replacement. After my weekend of reinstalling and testing other OS answers I decided actually no, I just want a full refund. I explained my general unhappiness about the unit and explained why I wanted a full refund and that I would rather have a tower or mini. If not Apple would have wanted to fix it.

If you really want the imac, tell that you only want a replacement and point them in the direction of the forum to prove that this problem does exist.

I have been having this problem on my imac 27" i7 (OX 10.6.8) for the past couple of weeks or so; for quite a while, I thought there was something wrong with my eyes! It seems to occur mostly during the first hour or so after start-up, or after waking from sleep.

Different from the flickering problem I had with my OTHER imac 27" a year or so ago, this is more like the screen is cycling through the brightness settings. I seem to notice this mostly on the left-hand side, but that might be a symptom of where the window is in relation to the monitor setup (window is near the right). Sometimes the cycling is very very fast, like a flicker, but other times it seems like a deliberate "step-step-step" cycle.

The other change that happened is that during startup, I have a strange "half blue/half white pixelated" screen temporarily as it loads the system; this seems to have happened AFTER I installed an app called "Air Display." I have turned this functionality "off" but I have not deleted/uninstalled from my mac.

Because the flickering seems to cycle through brightness settings--sometimes 10 steps at a time, as if someone is 'turning up the volume', it does seem related to either the software or firmware settings so I am hoping for a fix!

Same thing happening here. I am really annoyed because I spent a great deal of money on this mac. I bought the same for work and that one is ok and running great, with no signs of the flickering issue. My home one was bought a few weeks after the work one. What on earth is going on? I thought mac was to be trusted and any issues such as this were corrected since 09?

I thought I had fixed this problem but it is still continuing. Apple has replaced the led backlight power module and it still flickers. All fimware updates installed...still flickers. Wiped hard drive and reinstalled the OS. Still it flickers. I have a late 2009 model 27" screen. I now strongly feel this began after updating to 10.6.8. I'm no programer or expert but I believe 10.6.8 isn't playing nice with the updated firmware.