Q: New iMac 27inch screen flickering/tearing/shutoff

All right you two, back to your corners! We're all still recovering from yesterdays dust-up.

As far as our computers are concerned; I spent the majority of my working life as a production worker, and we had a saying on the line, "Never buy the first off the line, or the last one built on a Friday." I'm sure the Chinese have a better work ethic than that, but I think we're looking at a similar situation here.
There's a period of adjustment whenever a new product comes out, a time during which the normally routine nature of production is disrupted by the unfamiliar. On a production line it's routine that makes for perfection; and boredom, but that's a whole 'nother thing.

Unfortunately the first of the 27" iMacs, being a much anticipated new machine that would have been hugely in demand even if they hadn't been released so close to Christmas, were pumped off the line in massive numbers during that period of adjustment. We're lucky they work at all.

That's my theory anyway.

I don't work in production anymore, I'm retired. What that means is, I can, and do, whatever I want, whenever I want, for however long I want. And yes, I spend most of my computer time gaming. If that means I have no life, I can't tell you how glad I am of it.

Rick......

It's a common reaction. A lot of users report that once they either reboot, or just put the display to sleep, that the flickering does not return for hours, even days at a time, but most likely, it will return.

Did you zap the PRAM after running the firmware update? Many users have reported that their flickering issues were greatly reduced after the zap. I know mine were reduced to only a couple of occasions a day.

It would probably be best if you go ahead and call Apple and report the issue, and get a case #. In the event there is a recall, or a need for a replacement, you will already be on record with the issue.

What is the build week on your machine? Check your serial number. The third and fourth numeric symbols should indicate what week of the year it was manufactured. W8950, or W8951 would be week fifty or fifty-one.

Yes Cuenlain, you are right.

If you are retired, then you have earned the right to do pretty much as you please, even if it is spent "mostly" gaming.

At least you don't spend all of your time there.

Can you imagine the problems Apple had opening a new production line, in a new factory all at the same time. I spent about a decade in my early years working in similar production. Every time a new machine went on line, even though we had assembled and operated dozens identical to it before, there was always an adjustment period.
Compound that with language, and cultural barriers.

The fact that hundreds of thousands of these machines have been produced, and only a few hundred, maybe a few thousand have problems, that is remarkable.

SlickRick, I got my 21.5 from B&H in Manhattan. They shipped it to me in Florida. What week was yours made? Mine was Week 45. I got mine on Black Friday, but could not open until Christmas Day. I have Yellow Tinge on bottom Left, It's Slight, but it's there. Mine started flickering after a about a week. I ran Onyx 2 days ago on Auto (checked All boxes) & it Flicker stopped since then. I'm not claiming it's a Fix, but it got rid of it for me 2 days so far. I bought my Mac Mini & my Time Capsule from B&H as well. Great store.

My serial# is W8950.

B&H video is an awesome Store. They are 12 miles from house. I believe mine was built on week 50.

pazuita wrote:
Jon, I really don't want to burst your bubble, but......

"I was told that my replacement unit "will not have the problem""........

I heard the same words before I sent my week 47, and received my week 51 a little over a week ago. Guess what......it still flickers.

The truth is that there is no way to test for this problem other than using the unit, and staring at the screen for days, maybe weeks until it flickers.
No company would spend the man hours doing that, even if they could afford to. The replacement units may get extra testing, but that won't necessarily rule out the flickering since they don't know what causes it, and have no way of economically testing for it.

Since there is not an Apple Store within three hours of me, I didn't really have the option of repair, and the only reason I opted for replacement at this point was that the i7 also had a defective optical drive.
I still believe it's best to stall for time, and wait until the cause is determined, and cure released before swapping, or repairing a unit.

Sorry to hear that you received a second bad unit. I'm neither optimistic nor pessimistic about how my replacement unit will operate. I will continue to bring it back until I get one that works properly. I would like to stall for time but I do not want Apple to think this problem is acceptable. :^)

For everyone new to this forum with flickering iMac displays (or other problems), please visit the website below and enter in your information. That way everyone can see which iMacs are having problems.

http://imac.squeaked.com/results.php

I'm so conflicted about what to do! I have until this thursday to get a replacement no questions asked, but my imac 27' i5 has not had the flickering issue over the past 2 days. I was experiecing one or two flickers per day previous to that and once it actually blacked out for a second. However, this computer otherwise is absolutely phenomenal!! I think about the days when a Sun Microsystems Ultra-2 with 2 processors cost 15,000 bucks and I still can't believe I've got a quad core sitting on my looking gorgeous for a little over 2500!!

I'm a developer so I run a bunch of compiles thaty was spiking my core 2 duo macbook pro at nearly 100%, the same compiles run at little more than 15% on all 24 cpu!! Absolutely awesome!! I've already become "attached" to this unit so I really don't want to return it, however, if the flicker does turn out to be an omen of more severe problems I'd certainly rather have a new replacement unit than a refurbished or worked on unit.

Apple should do the right thing and when they finally isolate the problem, make good for everyone who has experienced this issue possibly by issuing a recall!

I just returned to my Office from my Christmas break and my Dec 13th purchased C2D 27" iMac has begun flickering and blacking out.

Up until now I only had one other incidence of this but there is something in common with both occurrences - cold. In both cases the office was very cold and the Mac had been off at least over night.

This could be something as simple as a dodgy solder or loose connector - a change in temperature will cause materials to expand and contract and depending on the exact nature of the problem could result in symptoms either on expansion OR contraction of a joint - ie as the temperature goes up the joint expands at the components push together for a better connection and for those that experienced the problem under higher temperatures, the problem manifests with a different joint being pushed apart by expansion and contraction.

I think it's one of those 'perfect storm' meetings of circumstance - a suspect batch of graphics cards from Manufacturer A meets the display panel problems from Manufacturer B meets the teething troubles of Manufacturer C's first production run.

Anyway, I'm taking it back to the store for a replacement on Saturday as in addition to the flickering, I've got the discolouration problem as well. (The store manager was cool about me exchanging the iMac despite being outside the 14 days).

SlickRick, Born in Manhattan & lived in Flushing, Queens most of my life. Moved to Florida, 10 Years ago.

Third Day, Still no Flicker since I ran Onyx. I'm still not convinced, but something Onyx did, temporarily for 3 days, so far, got rid of my my 21.5 Screen Flicker.

ennuikiller, I understand your feelings. I am attached to mine as well. Everything works perfectly except "Yellow Tinge" & I had a Screen Flicker issue that is gone now, after running Onyx. It may be a coincidence, but 3 days after running Onyx, no screen flicker. The Yellow of course is still there. 21.5 Week 45.

I received my new iMac December 28th. It's a week 52 build and I experienced a full week without issues (and assumed I was lucky to have a "fixed" version). Well today my luck ended and my computer also began flickering and momentarily blacking out. I phoned tech support who sent me a "Capture Data" program to run during the flickering episodes and to email back to them once I have done this. My computer has since not had the issue....

Ok that Capture Data program was not intended to fix it, but give Apple the symptoms of your iMac, correct? And now your Screen stopped flickering? Mine stopped Flickering after I ran Onyx in Auto mode. Three days without a Flicker. Everyone says it's a coincidence. Well whatever it is, it Worked at least for now. If it starts to Flicker again, I will run Onyx again & then I will know for sure if Onyx helped. I know Onyx just deletes files & runs Scripts, etc...but again my Screen has not Flickered since I ran Onyx 3 days ago. Now if I could only find something for the Yellow Tinge. L.O.L. I know THAT is not going away with any Software.

I am thinking about purchasing an iMac 27" I5. I have read most of the threads concerning the "flickering" issue and have decided to wait a few weeks to see if Apple solves the problem. the following are a few thoughts/conclusions from what I have read so far. Whether they are correct or not -- time will only tell. Though the data is not "normalized" (# of problems per particular unit sold), it would appear that the the number of problems seem to be less in the two weeks or so. Secondly, though there are many ideas as to what the problem might be, my observation is this: the problems seem to screen related most predominately on the 27" models. Based on a few comments concerning repair, it seems that the problem appears to be some (not all) poorly manufactured screens and or their connectors. It appears that they were more numerous after week 41 and have declined after week 50. The public data is not large -- but it might be telling. If this is true, Apple may have taken out some of the faulty units out of their inventory, but they probably did not get all of them. And the manufacturer of screens/cables may have improved their performance, but not completely. Thus, we still see some "bad" units. As for the firmware update -- that may have been needed to resolve a related issue with ATI video processor -- but not the broader issue that has emerged in the manufacturing process. That's my "guess" as to what is going on here.