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

Sry Dino....I should have stated "27"+21" new iMac saga" instead.....

Megallis wrote:
Please tell me. What is the V-sync cable?

It is short for "vertical synchronization cable". All displays get a V-sync signal from the video card that says when to redraw the screen. My guess is that the bad cables and/or displays don't properly relay or interpret this information, causing the screen to shift so that the Dock and other items aren't in the right place. That is one of the more extreme symptoms of the flickering/blackout issue. My guess is that the blackout is occurring when the V-sync signal timing changes erroneously, which is fooling the display into thinking the display settings have changed, when in fact they have not.

To update everyone regarding my situation, I received my first replacement 27" iMac i7 yesterday around noon. It is a week 02 model. I've been running it hard since then to see if there are any anomalies. There appears to be one dead display pixel and three stuck iSight pixels, and the display has a small amount of uneven lighting to the left of center that is only evident when the background is bright white and the back lighting is turned up all of the way. There is a very faint yellow hue to the bottom 1/3 of the screen, towards the right. I can also hear the intake fan on this one, whereas my previous flickering iMac was completely silent. I would rather hear the fan to know that it is working. No flickering/blackout/screen offset issues though!

I will post another response in a few days to indicate whether all is still well or not.

Update: I just encountered an issue where the display backlight dimmed in a rapid pulsating manner for about two seconds. It happened right as I was starting to empty the trash. I recall a couple other people mentioning this issue with their replacement iMacs. If this continues, I am getting a refund.

Picked my new 27 inch up today from Yokosuka... no sleep for my Mac, runs as hot as the 24... no issues so far...

Doing a "Secure Empty Trash" was the first time I noticed mine do that. Screen Kind of dimmed in & out.

Eck-e-thump chaps!!! What a fine mess I have got myself into now. So sorry to hear about your challenges with the iMac.

Ordered a 27" back in December 2009, quoted delivery date 13th of January, told that the delivery was delayed by 7 days and now not before the middle of February.

Subsequently, "read all about it" on here. Should I consider myself lucky that the delivery is delayed and wait to see if Apple have corrected their design/build faults; or, pull the plug now and blow the 2k on dirty women?

First of all its the 27th, and secondly give me a break, they're not going to announce a new product with festive fanfare and then mention problems with the iMac, ridiculous.

Sent my iMac back to B&H (store in NY) for an exchange. It arrived there last Friday. Wasn't checked in as being returned until today (Tuesday). That's besides the 5 days it took to get there from here (Florida). Now it takes 3- 4 days for Paper Work to send my replacement. It probably won't get to me until the end of the month. If it is another iLemon, I don't think I can go through another month just to do yet another exchange that I'm not sure will be perfect. Just Venting Here!

UPDATE 3rd mac

Ok..an apple techician said to me : "We don't have a fix yet for the flickeringproblem"... so... no speculations anymore... there isn't a fix.

They've refused a refund and said "go to a service point".

I liked apple service before , but this is not the service i paid for.

The 27" was a dream... but after 3 bad imacs.. it's just a buggy intel-pc with a great design. Clever...

THANK YOU APPLE !

For sure they do everything to fix the screen problems before Jan 27. There are some rumors in the press that Apple could announce a new 22" iMac Touch. In that case it would be a must for Apple to solve the screen problems first.

just to say as one of the top 5 trollers (according to some) or posters in this thread:

im officially bowing out of this thread now! im done with imacs and have been in touch with exec relations....... im switching to a macpro now and we have come to a deal for it.

i will say that apple have been amazing throughout all of this and very professional.

their customer relations team are outstanding! i was told that theyve located my imac and its winging its way back to cupertino to apples engineering dept. he also said that rest assured their working on it and also said that hes dealt with a few of these imacs with probs now.

so ive had my moan and also credit where its due! back to being a happy camper

good luck to all with these issues

just another poor i7 27" with flickering/screen shifting...Mine happened after the firmware update. Week 45 production.

im officially bowing out of this thread now!

Hey sparkie! It's a great pity that you're out. We loved your comments!

thanks citrus, ill still be checking in!!!

but now im not having an imac i dont see any point in posting any longer, would hate to be branded a troll

sparkie......

You oughta know by now, what is going to happen.

You will quickly get your MacPro, and get it set up, and of course, operating perfectly as most Macs do.

A week later, Apple will introduce the new line of Mac Pro's...... Quad/Quads........with 4 i7's, and a new videocard with a zillion gazigabytes of ram/BlueRay/SATA etc etc etc.....

They will also probably have all of the i7 problems corrected by then.