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

hkrause wrote:
Apple has reworked the video card? I thought Apple was outsourcing the video cards. Seems unlikely Apple would be "reworking" a video card made by someone else, no?

I made a comment on that same sentence some time ago as well. I honestly don't know if that email is real or somebody's idea of a joke, but if it really was sent out by an Apple reseller, I am really curious about what they mean by reworking the video card.

Does it mean that they have fixed the contacts on the card so that it is better seated in the slot?

Does it mean that they are exchanging the troublesome ATI Radeon 4850 card for a different card altogether?

Does it mean that they have devised a software/firmware fix?

Does it mean that the actual manufacturer of the card is somehow redesigning the card?

Exactly what does "rework" mean?

Curious minds -- who have spent thousands of dollars on these machines -- want to know.

Update on my situation.

I had issues and tried to self-diagnose with the help of this board. At times I thought it was fixed, only to have it return.

Well, I ended up just returning the machine in exchange for a new one. The new one has had no issues at all and its been ~3-4 weeks. I think it's a hardware issue and its hit or miss.

You confirm 100% you don't have the yellow tint on the lower half of the screen besides no flickering?

Thanks!

DavidsonTsai wrote:
Update on my situation.

I had issues and tried to self-diagnose with the help of this board. At times I thought it was fixed, only to have it return.

Well, I ended up just returning the machine in exchange for a new one. The new one has had no issues at all and its been ~3-4 weeks. I think it's a hardware issue and its hit or miss.

What's your serial number? I read about an user received an iMac directly from China... but it's flickering! I don't think it's fixed...
What about the yellow tingue?
Thanks!

P.S. Christmas is coming and I'll purchase it next year... New year, new iMac in every sense! I wish everyone here...

I don't buy this alleged report. Plenty of C2D models are afflicted with these issues as well.

Are the effected C2D's with the 4850 or 4670? It could effect both GPU's like with the 8xxx series being faulty with NVIDIA.

Message was edited by: quagmire2

Serial Number W8945...
Been using this machine for 3 weeks now. It has been absolutely flawless.
And I guess others have my experience. This makes me think that the problems folks are having could be due to dodgy assembly in the factories or faulty RAM modules.
Well just my guess:-)

When you say flawless you mean no yellowish cast in the bottom of the screen? Sometimes it's hard to see...

Thanks!

I was stopping by one of my Apple reseller today and played with the demo iMac 27" C2D, the base model, "lowest" spec. Obviously the thing had been running all day and the back of the display was insanely hot(!), no good for electronic components.

After two minutes of Safari started the flickering, black horizontal flashing bars randomly for about a minute. I know the unit has been there since November so it's not of the newest batch, but anyway.

Planning to put my online order for i7 but this ain't making it easy at all.

No yellowish cast anywhere. In fact the screen is just amazing. All these 720p 1080p movies etc look like 3D. And this is the first iMac I have had that can play 1080p.

Ari Jr wrote:
After two minutes of Safari started the flickering, black horizontal flashing bars randomly for about a minute. I know the unit has been there since November so it's not of the newest batch, but anyway.

I'm curious. You state that the demo unit has been at the store since November. That being the case, it is probable that store employees -- as well as other customers -- have had ample opportunity to try it out.

Now, if you were so quick to notice the defects, doesn't it stand to reason that the store employees and other customers would notice them as well?

Assuming that this is the case, why in the world would any Apple reseller leave a defective unit on display? It doesn't make sense.

Did you mention the defects to the store? If so, what was their reaction?

Thanks!

Thought I'd chime in with my experience thus far.

Received a 27" i7 on Nov 27th. Been using it everyday since then. No screen issues until yesterday. Started getting flickering and then my screen would actually freeze split with the bottom 2 inches displayed above the top. Really strange.

Called support they had me do a PRAM reset....no issues from noon until 6PM last night.

Turned my computer on at 8AM this morning started having the same issues by 10AM.

Called support - they had me re-install OSX. No issues yet.

We will see what happens...I'm assuming mine will have to be replaced as well.

Joe

Warren Beasley wrote:

Ari Jr wrote:

Now, if you were so quick to notice the defects, doesn't it stand to reason that the store employees and other customers would notice them as well?

That's the thing. I don't think people that aren't specifically looking for these defects (at least the yellowing of the screen, the flickering I can understand) are going to see them. Probably another reason why Apple has not released anything official yet.

Thanks Haddy... So flawless iMacs do exist then... Everyone deserves one in that case.

Does anyone out there have any idea of just how many of the 27" models Apple has shipped so far?

This site has a collation of stats that indicates, on these forums, 179 cases have been reported of screen flickering, affecting all models of the 27 inchers, including i5's, i7's, and core 2 duos as well.

http://www.computerworld.com/s/article/9141894/Applecustomer_collates_27_in._iMac_displayproblems

From the number of posts, it would seem to be far more than that.

Even if you multiply this number by a factor of ten, it still remains a very small portion of the machines Apple has sold, which is easily in the tens of thousands, if not much, much more.

Apple will not likely issue a statement until they are absolutely sure that the issue is resolved, and most units affected either replaced, or repaired. Right now, they can tell you nothing, since they are not absolutely sure what the problem is, although the techs I have spoken with are all leaning toward a problem with the display itself, not the graphics card, since multiple users have used external monitors which did not exhibit the flickering issue, while the built in display did. Most likely a graphics card issue would affect the external as well.

Nor is the problem temperature related, it occurs randomly at low and high operating temperatures, and only a few users have been able to reproduce the problem by adjusting the brightness.

There are also numerous reports across the web of windows users who have similar flickering problems with various i7 configurations, so this problem may not be limited to Apple hardware.

It is doubtful that Apple is intentionally shipping defective units as some have suggested. It is simply that they don't know what causes the problem, and that the problem only affects a small percentage of units currently being shipped.
To cease production of a new model with a very low failure rate in not a rational option, and Apple will most likely continue shipping, while trying to pin down the actual cause of the flickering, and then take corrective action. Six months after the problem is solved, and all defective units replaced, perhaphs then, Apple will issue a statement.

Until then, Apple still has the best Customer Support, and Warranties in the industry, and I believe anyone purchasing a 27 inch model will be pleased with the end result.

My i7 will be shipping back as soon as I receive the replacement which should ship within the next week. Apple Support has been great all through the process.
Not only do I have the flickering problem, but also have a dead optical drive.

Even with those issues, this machine is incredible, and far superior to any windows box I have ever used, or owned.