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

Hi everybody,

Just an update (and a recap) about my story.

I saw the flickering/black screen 3 times:
- day 1, a few hours after the first (cold) start. Did nothing, just go to sleep.
- day 2, a few hours after a restart from Windows, but don't remember exactly when. A restart solve the issue.
- day 9, one and half hour after a cold start. A restart solve the issue.

It is day 16 now and no more flickering even when extensively use of CPU or GPU, running virtualization software, etc.

Flickering/black screen occurs:
- with Airport ON and OFF
- with my iMac plug on UPS
- with no extrem temperatures, either low or high.

and doesn't occurs:
- on external display in extended mode
- on external display in mirror mode

I also run Windows on Bootcamp a few hours without flickering but as this problem occurs rarely on my iMac, it doesn't prove anything.

Nice week-end.

I'd like to add that my week 46 i5 started flickering today. (had it for about 2.5 weeks now)

ArMyZ wrote:
Is there some user here using bootcamp with windows who experienced the flickering issue too?

I guess the problem is that people don't use Windows on Bootcam long enough on their iMacs that they could really proof that there was no problem.

pors wrote:

ArMyZ wrote:
Is there some user here using bootcamp with windows who experienced the flickering issue too?

I guess the problem is that people don't use Windows on Bootcam long enough on their iMacs that they could really proof that there was no problem.

Yes, maybe too. I hope that in windows/bootcamp this issue is absent so it could be quite sure it's a software issue and not a hardware fault.

After two conversations with Tech Support over the past two weeks, I was told that the next step was to take my i7 into my local Apple store for a hardware test. I asked if I should bring everything along, and was told no...just the machine itself. I made an appointment and showed up this morning. The Genius Bar guy asked me why I hadn't simply returned the machine, since I'm within the 14 day window. I responded that Tech Support had counseled me to bring my computer to the store for the hardware test. GB guy told me that they would need to keep my Mac for 5-7 days. At this point I told him that I wanted to return it. He told me that I'd have to do that through the Apple Online Store. I phoned while in the Apple Store to make sure that I could return it. Apple Online said I could and would soon receive an RMA email with a FedEx mailing label. Both have arrived, and I'm taking my machine to FedEx as soon as I complete this post. Apple estimates my replacement i7 will ship on Dec. 29, arriving Jan. 4. We'll see.

Hi Everyone,

I've spent almost over an hour going through this post and yes, the flickering has occurred on my i7 for the first time after approximately 20 hours after unpacking. (googling found me this post)

I switched it off when I noticed the first very quick blackout and a few split-second-flickers right after and it hasn't happened yet after around one hour of PhotoShop and YouTube-ing simultaneously... Oddly enough it happened everytime I moved something around in PhotoShop.

So I ask, +has ANYONE experienced slight flickering in the beginning stages and it went away after a while?+ Or is this flickering basically sort of just the tip of the iceberg?

I'm just bracing for the fact that I may have to send it in...

Thanks in advance and hoping for the best,
s0l

Message was edited by: s0lar

So, I delivered my Quad Core i7 8GB/2TB 27" iMac to Fedex. When I came home, I wrote this poem:

Ode to a Quad Core

The day was dark ‘fore you arrived
But sunshine did you bring.
You’ve spurned me now and travel back
To Apple whence you spring.
I hope your innards they are fixed
When you return to me.
If not I’ll ***** and moan and cry
And to my grave I’ll flee.

Nice one!

There is no way in h* I'm giving this baby back. Even if it turned out that the problem was unfixable, and apple was withdrawing the whole product line!

I'm so in love...

@ArMyZ

do you read my post ???

first W8945:
OS X -> flickering and blank in the first 6 hours of use
XP -> bluescreens, heave graphic problems
Windows 7-> restarting of graphic system round about every 15 seconds
Vista 32 -> restarting of graphic system (not so often), here I was able to play a game (Stalker c.o.P)

only in OS X I hade some flicker-free days.

replacement W8950:
OS X -> no problems in 12 hours of use
XP -> no problems in 6 hours of game and os testing
Windows 7 -> no problems in 12 hours of internet, programming and gameplay

betronic wrote:
@ArMyZ

do you read my post ???

first W8945:
OS X -> flickering and blank in the first 6 hours of use
XP -> bluescreens, heave graphic problems
Windows 7-> restarting of graphic system round about every 15 seconds
Vista 32 -> restarting of graphic system (not so often), here I was able to play a game (Stalker c.o.P)

only in OS X I hade some flicker-free days.

replacement W8950:
OS X -> no problems in 12 hours of use
XP -> no problems in 6 hours of game and os testing
Windows 7 -> no problems in 12 hours of internet, programming and gameplay

I read it, yes.
Mine is w8946 and I got it 3 times only in 3 weeks. Last time this morning, just powered on (cold) just with a safari session. Then I rebooted and I'm working with Photoshop, uploading and downloading, ftp sessions, farmville fullscreen, since 11 hours and I had no problem at all.
How weird:\

My parallel windows 7 works perfectly (no bootcamp tried).

I'm waiting for Apple Official Announcement.

so after reading all these post on this discussion, i noticed something.
the only time i get screen flickering and black out is AFTER my imac has been waken up from sleep mode.

if i do a normal start. and i can work for hours without going to sleep. no problem. includes intense final cut, photoshop, and watching HD contents.
once i put to sleep. the next morning. screen flicker starts. and follow by black outs. by just browsing online and doing easy tasks.

so i believe its NOT the GUP temp and all that..
it has to be with something in the power supply or system after the computer has been waken up from sleep.
did the latest update on sleep/wifi setting.(release on 12/10, i believe) problem still exists.

hope my input helps.

imac 27" i7 2.8 quad
week 47, received on Nov 27 shipped directly from apple in shanghai

s0lar wrote:

I've spent almost over an hour going through this post and yes, the flickering has occurred on my i7 for the first time after approximately 20 hours after unpacking.

maybe this post is infected wit the "Flicker Virus"
My flickering started within couple hours of usage. I don't believe it's related to how hard you push your Mac with heavy tasks. It's something what appears and goes like bad weather. I did not notice any problems other than flickering and black-outs, but once i contacted apple, they offered to replace the computer which I am still using and it works fine, despite the occasional flickers. I
Some people say that the flickering only occurs when they come back from 'sleep mode'. in my case it does not make any difference, and normally it starts flickering after turning it on.

My new mac week53 is on the way and I hope it will not have any problems. Otherwise I guess i will return it and wait a few months for the new generation which i hope will have the BlueRay as well causing another problem

camereo wrote:

My new mac week53 is on the way and I hope it will not have any problems. Otherwise I guess i will return it and wait a few months for the new generation which i hope will have the BlueRay as well causing another problem

Week 53? What planet was your iMac made on?

Week 53 does exist for 2009... but it starts Dec 28

http://www.tuxgraphics.org/toolbox/cal_year.html

- Karen

karen_forums wrote:
Week 53 does exist for 2009... but it starts Dec 28

http://www.tuxgraphics.org/toolbox/cal_year.html

- Karen

Hello Karen. Thanks for the nice calendar java applet. I don't know if I will actually ever use it for anything, since I have a small desktop calendar on my Mac called PandoCalendar, but I stashed away a copy of the java calendar for possible future use. Of course, the week starting on Monday -- instead of Sunday -- does throw me off.

On another topic, I've noticed that in several of these threads, some people have mentioned having bad pixels in their iSight camera.

Is this somehow different from actually having dead or stuck pixels in the LCD monitor itself? I have never used an iSight camera, so I am unfamiliar with this.

Can someone please explain to me step-by-step how to check for dead pixels in the iSight camera?

This is another test I will conduct when my new i7 iMac finally arrives. Today marks day #31 since I placed my order.

Thanks!