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27'' LED Cinema Display flickers when powering MBP and dimmed down

The 27'' LED Cinema Display flickers (backlight flickers) in the following situation:

* The display powers an MacBook Pro (e.g. later 2010).
* The MacBook Pro is fully charged (i.e. power is not used for charging).
* The MacBook Pro performs some GPU intense task (moving the mouse over the dock with magnification enabled).
* The brightness of the display is dimmed down to one of the lower settings (one or two "bars").

The problem disappears if the MBP is powered by an independent charger.

We reproduced the problem with two different MBPs (13'' and 15'') and two different displays.

MacBook Pro 13 (MBP5,5),MacBook Pro 15 2.4 (MacBookPro3,1), Mac min CD2, PowerMac Cube, PowerBook G4, Mac OS X (10.6.5)

Posted on Dec 2, 2010 12:29 AM

55 replies

Feb 7, 2011 5:38 AM in response to Christian Fries

Just adding that I'm in the same boat as the rest of you. I just received a refurbished 27" LED Cinema Display which is connected to a 13" MacBook Pro, which I'm using in "closed" mode. I had noticed the flickering and lower brightness settings and so decided to check out the support forums.

NOT powering the MacBook Pro from the Cinema Display resolves the issue (as others have noted) although that tends to mitigate part of the benefits of using Apple's Cinema Display over less expensive competitors.

Hopefully someone at Apple is looking at the forums since their isn't a an option for "displays" at www.apple.com/feedback/ . This issue needs to be resolved so the product can be used as described.

hausersn

Level 1

0 points

Feb 14, 2011 3:07 AM in response to Christian Fries

Hi,

I brought my display to an apple service provider which first changed the logic board. This didn't solved the problem. Then he changed the power supply. Now it seems, that the flickering is gone.

Regards,

Stefan

tssn222

Level 1

0 points

Feb 18, 2011 6:44 AM in response to Christian Fries

Is this something that affects all such setups, or are there people with this setup who do not get this problem (i.e. indicative of a sporadic hardware issue)?

hausersn

Level 1

0 points

Feb 18, 2011 8:00 AM in response to tssn222

I tested my display with three 2009 and 2010 MacBook Pro ( all 13"). It flickered with every mbp.

plasmo

Level 1

15 points

Feb 18, 2011 10:19 PM in response to Christian Fries

My 24" LED ACD flickers when connected to my MacBook Pro 13" sometimes. Cannot determine what is the cause.

I have tried not using charging my MacBook, removing USB devices, software updates, connecting displayport before/after turning MacBook, still same problem.

Mar 11, 2011 5:51 AM in response to Christian Fries

I noticed, that the flickering only occures when I'm using my 9400m in my Late 2008 MacBook Pro, If I switch to the 9600m GT the flickering is gone! I have NO! idea why :/

Mar 24, 2011 10:24 PM in response to Jip van Kuijk

I have the same issue. Though, my 9600 almost gave me a heart attack, because it caused my whole bottom screen to flicker like mad and freeze my machine.

josemari

Level 1

110 points

Mar 27, 2011 2:27 AM in response to Christian Fries

Seems like such a small issue for so much complaining. Use six bars and/or use the separate charger that you already have, or return the display and go back to your old matte monitor. 😟

Apr 8, 2011 5:12 AM in response to Christian Fries

I can replicate this problem consistently with my 27" LED Cinema Display purchased in January 2011.

When the 27" LED Cinema Display is powering my Macbook Air 11" via the built-in magsafe charger, AND the brightness control is below 50%, the display flickers.

Removing the magsafe charger stops the flicker.

Plugging the magsafe charger back in, the flicker returns.

Turning brightness above 50% brightness, the flicker disappears.

The question is - has anyone got a 27" LED Cinema Display that doesn't exhibit this fault?

bewst

Level 1

0 points

Apr 14, 2011 11:27 AM in response to Christian Fries

For what it's worth, I have this problem and using an external charger instead of the display power does not fix it for me.

bewst

Level 1

0 points

May 5, 2011 11:11 AM in response to bewst

And furthermore, today's software updates don't fix it for me 😟 !

Jun 15, 2011 4:07 PM in response to Christian Fries

I just got a new 27" LED Display...

Actually, I got FOUR! :/

First one had multiple sub pixels. The replacement had bunch of dust under the screen and dead pixels in the lower left. I gave up and decided to go to a local Micro Center, where one of them had blue sub pixels everywhere on the right side of the screen, roughly two inches off the bezel. Finally, the fourth one was perfect; however, I've noticed the flickering too!

I'm using it with the 2.8 Quad Mac Pro and it flickers until setting 6. At setting 7, it goes back to normal. I believe only one of all four didn't really flicker. No help but to deal with it I'm assuming 😟

I'm just very disappointed with Apple's quality control. If I wanted a monitor with this many faults, I would've saved myself money and gotten a $200 piece of junk, not a $1000 display!

odysseus

Level 3

948 points

Jun 19, 2011 2:40 AM in response to reRESERVEDFX

Has anyone taken this problem up with Apple tech support and/or sent their display in for repair??

vonmitch

Level 1

4 points

Jun 28, 2011 2:02 PM in response to Christian Fries

Same here!

13" MBP (late 2009) & 15" (mid 2010) + 27" LED (April 2011)

Any solutions from Apple?

odysseus

Level 3

948 points

Jun 28, 2011 6:03 PM in response to vonmitch

The first step is to call Apple. I was told to unplug my display and reset the SMC on my MacBook Pro. If the problem recurred after that, the tech support agent informed me that a repair would be in order.

27'' LED Cinema Display flickers when powering MBP and dimmed down