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

As they say in any business:

"You are no better than your worst supplier"

and in another vain

"You are no better than your worst designer"

I think Apple is faced with a little of both here.

I sure wish Apple would step in here and put an end to all this speculation and tell all of us what is going on. There us just too much at risk with Apple's reputation to let this continue.

Yes, you are close!

I would think that the yellowing is caused by either defect in the assembly of the LCD panel itself or it could also be a problem with the color consistency of the LED back lighting.

In "regular" LCD TVs the light source are fluorescent tubes above, beside and sometimes behind the LCD. A white diffusion panel behind the LCD redirects and scatters the light evenly to ensure a uniform display.

In LED based LCD TVs it's LEDs that provide the backlighting.

White LEDs can be manufactured with different color temperatures.

You can have white LEDs that are more on the warm side (more yellow) or that are more on the cold side (more blue).

You have a number of LEDs aligned next to each other to make a strip of light in the different positions. If some or all of these LEDs are of the wrong color temperature, you would get uneven colors.

And since the LEDs are white and only white (it's the LCD that as color in it, the back lighting is always white), that color temperature difference is visible mostly with white images.





I have seen similar problems in high end show lighting equipments where the color of the LEDs would differ from one unit to the next when they should have been an exact color match. It turned out to be a bad batch of LEDs that the makers of the lighting equipment had received from their LED supplier.

These are very complex technologies and it's easy for end users like us to blame Apple and say it should have been fixed a long time ago.

For me the real problem is not the time Apple is taking in fixing this.

The real problem is the fact that they are not telling us anything!

Be straight forward and tell me "we OFFICIALLY acknowledge there is a problem, we are sorry and are working on a fix and we will have a solution for you ASAP".

Then I would wait for the fix and relax knowing it will be here soon.

But now we are left in the dark with vague and inconsistent answers from all different sources.



Very annoying!

Message was edited by: Nexus600

Message was edited by: Nexus600

Nothing Official has been stated by Apple. But a Tech called me yesterday & said Apple does not know what the problem is & so of course does not have a Solution. They estimate 3 Weeks or Longer for a fix. This Tech called ME to give me this information. He was very empathetic & blatantly honest. I thanked him for his honesty & he said someone will get back to me, when they have a solution.

In one sense I would like to agree with the tech and in another there is much more to the story. This problem has been going on for months in one form or another. Having been an electrical engineer for 35 years I can assure you there is enough talent on this problem to find the cause. The real problem is to find a solution with the least amount of financial impact. The one solution they are facing now is returning ALL the units and replacing some major component. This is financially unacceptable and therefore an immediate solution is not available. Apple is a business and a good one at that. They are expected to meet customer requirements while providing a reasonable return on net assets.

Simply said; we are all stuck awaiting the best technical, financial and business solution to this condition that acts in the best interest of Apple Inc. I personally can wait but for those with a new IMac that is a personal decision based on your willingness to trust Apple to act in your best interest.

Thanks for the in-depth explanation, Nexus600; it is much appreciated.

The way you explain it, it sounds like there may possibly be a firmware way to overcome this problem, without everyone having to get their v-sync cable and LCD panel exchanged . . . which would be a major hassle for us, and Apple, both.

Would you agree, or no?

That's just good customers relations.

Nice of them to give you a call to update you on the situation.
Still you and all of us are no better off!
We don't know when it will be fixed or how.
Will we have to take our machines back? Will it be a firmware fixe?

If by now they haven't been able to narrow it down to hardware or software, then man we are in for a loooong ride!

They surely have enough information at this point to issue a statement!

I find it unbelievable, that our discussions are the source for many published articles all over the world. When you google under "imac 27" (News) you can read, what we're saying here. They publish our phone calls with Apple. CRAZY!

Warren,

I'm afraid I don't agree.

If it's a bad batch of LEDs ( wrong color temp.), it can not be corrected by firmware. Once a LED is made, you can not change its color. The color of the light source in an LCD screen remains the same regardless of the color adjustments you make when you calibrate or adjust the colors of your screen.

Those adjustments are made at video card level and as far as I know, you can not adjust the colors on a spot by spot basis.

I mean if only some of the LEDs in a screen back light are more yellow than the rest you would have to be able to apply some sort of color correction on the part of the LCD that these bad LEDs are illuminating.

If ALL of the LEDs in a screen are too yellow in color temperature, than it's an other story. That could be corrected by calibrating the screen via the video card drivers since the correction would be applied to the entire screen.

If any of these so called Technological Bozo Writers had bothered to read the actual Posts & not just the Thread Titles, they would know it's not only the 27" & the ATI Card that is the problem. So no, I don't think there reading the posts by members, just the titles.

Here's TechNewsWorld: "The 27-inch iMac has a problem with the AMD ATI graphics card," said Broadpoint AmTech analyst Brian Marshall. "They should have stuck to Nvidia."

Last I checked Writers were suppose to do research before they wrote an article. Well good writers anyway.

Dino,

See my post on page 251.
http://discussions.apple.com/thread.jspa?threadID=2212682&start=3750&tstart=0

I commented on the fact that they publish articles with out any confirmations of things they read on the web!

Writers on independent web sites do not follow the same ethical rules that journalists from "real" news papers or news organs do.

Many of them do a good and serious job, but some of them will write and publish stuff without any sort of serious research or background check on a story.

Nexus, Yes I read your Post. "Allegedly" They can say ANYTHING they want without having any knowledge of what they are talking about. It would be like me writing an Article on building a Rocket.
I wrote an Editor a reply, to her inaccurate article a month ago. She of course did not Reply.

I have been chomping at the bit to purchase the iMAC i5 since introduction in October. I always believe in waiting for any tech product to have assembley bugs worked out first before purchase. This one though seems to be an unusually long correction process. My understanding is assembly shifted to a plant in Shang Hai and I presume may create some communication/control issues for problem solving. (I don't mean because they speak Chinese, but rather the distance to monitor assembly controls). I use the same "dome based, 15" screen, G4" iMAC, which I bought in 2002-2003. I still love the machine to this day and it works beautifully other than keeping up with HD Video transfer/play(YouTube) and download which challenges the processor, or that it doesn't qualify to run software above what is compatible with OSX 10.4. I probably won't buy a new iMAC until ALL issues are resolved. I also wanted to share a story of an issue I had with my iMAC around 2005. It was a mouse issue where after an hour or two of working on the computer the cursor on screen would jump all over or stop responding completely. For weeks talking with MAC Tech, who was wonderful by the way, we did trouble shooting on every conceivable process of the computer. Reload software, firmware updates, hardware tests. I found this same issue mentioned in threads in discussion group and was ready to rip my hair out after having no resolve for weeks. One day while working and attemping to move the mouse cursor it again froze up and I pick up the mouse and turned it over in my hand and was going to curse it when I noticed a tiny brown spot on the underside of the white cable coming out of the top of the mouse. Under direct light with a magnifying glass I realized the wiring had a kink in it and was starting to burn through the wiring sheath and shorting out the signal from the mouse to the computer. After explaining this to the tech they immediately reported this problem to tech as the solution sent a new one out and the problem was solved. The thread I was on had many people respond to my example realizing the same issue while Apple had not been able to detect it as this simple problem thinking it was a problem in the main computer itself. So I am wondering if the issue is so elusive because it may be something as simple as a poorly welded transistor, cable, wiring harness etc.. It just makes me more patient in waiting for a fix though I am still chomping at the bit in frustration. It also makes me realize how challenging it can be to diagnose tech.

I am new to the boards on Apple, but I thought this might be helpful. I actually am looking to buy one of these 27" (I am new to apple computers aswell) I am a diehard pc fan, and I am looking for something new to fool around with, so I thought why not an IMac. Well I was doing research and found that there are issues, and it lead me here.

To sum this up, I called Apple ( 5 minute wait, VERY impressive) and talked to a guy about this issue. He said, "Apple is aware of this issue and our tech team is working on a fix and will be fixed within the week." I don't know if this is true, but that is what he said. I asked questions about buying an Imac for the 1st time, and some questions about prices and whatnot. I am not going to buy an Imac 27" until I know that there won't be an issue.

Some more news/non-news on the problem.

http://tinyurl.com/y95dlkc

I feel very badly about all the issues those of you who purchased these new iMac's are having. Hopefully, a solution will soon be found. I cancelled my i7 back at the end of November and very glad I did.

Best of luck to all of you,
Phillip

Do you have a good sense of humor?

I hope so!

Check this out:

http://www.mediafire.com/imageview.php?quickkey=nimitztzmmm