New 27" Thunderbolt Display Flickers when attached to new 27" iMac

I'm using a new 27" iMac. I require a dual-monitor configuration so yesterday I purchased a new 27" Thunderbolt display and plugged its built-in Thunderbolt cable into the Thunderbolt port of the iMac. I now have a huge desktop space that spans two monitors. With that in mind…


At least once every few minutes the new Thunderbolt display blacks out (i.e. flickers) for approximately one second. The symptom is very similar to what a Windows-attached display does when the screen resolution is changed. A quick Google search indicates others are experiencing the same problem although most complainants are using a MacBook or Mini, not an iMac.


Apple posted a firmware update for the Thunderbolt display a few days ago. I installed it successfully but the problem remains. Any advice?

iMac, Mac OS X (10.7)

Posted on Sep 24, 2011 4:40 PM

Reply
190 replies

Dec 20, 2012 11:31 AM in response to d-mon-k

Well, I posted elsewhere and got referred here. Sounds like the same problem, though. Also, the poster before me stated he had the same problem on non Thunderbolt displays.


My particulars are


Hardware Overview:


Model Name: MacBook Pro

Model Identifier: MacBookPro8,2

Processor Name: Intel Core i7

Processor Speed: 2.5 GHz

Number of Processors: 1

Total Number of Cores: 4

L2 Cache (per Core): 256 KB

L3 Cache: 8 MB

Memory: 8 GB

Boot ROM Version: MBP81.0047.B27

SMC Version (system): 1.69f3

Serial Number (system): ----------------

Hardware UUID: 3C4B2FB2-7E56-5E33-8D94-7469266C6C83

Sudden Motion Sensor:

State: Enabled


<Edited by host>

Dec 20, 2012 11:31 AM in response to Cosman

Same issue.

I'm on a 5 hour old MB Pro 15 Retina and TBD.... fun.

Model Name: MacBook Pro

Model Identifier: MacBookPro10,1

Processor Name: Intel Core i7

Processor Speed: 2.7 GHz

Number of Processors: 1

Total Number of Cores: 4

L2 Cache (per Core): 256 KB

L3 Cache: 8 MB

Memory: 16 GB

Boot ROM Version: MBP101.00EE.B02

SMC Version (system): 2.3f32


Thunderbolt Display:

Display Type: LCD

Resolution: 2560 x 1440

Pixel Depth: 32-Bit Color (ARGB8888)

Display Serial Number: ----------------

Main Display: Yes

Mirror: Off

Online: Yes

Rotation: Supported

Connection Type: DisplayPort


<Edited by host>

Dec 22, 2012 12:39 AM in response to orchetect

definitly NOT synchronous. They will flicker independently of each other, with *perhaps* greater frequency on the display running full screen youtube video.


The screen flickers occur once about every 2-5 minutes, sometimes less frequent. It definitely happens, though, and for a display of this price, should funciton without this issue.


I unplugged all USB devices and that didn't prevent it. I changed the desktop image to basic color and that didn't mitigate it either. If the memory doesn't take care of it, the displays are getting returned.


I'm planning on running a memory test overnight on the 16gb, just to check.

Dec 23, 2012 8:24 AM in response to William_o

Wow... I wonder if it's something about the power draw of that extra 8GB of RAM that messes with the TB signal.


I've gotten worse here on day 3 of the new MBP Retina Mid 2012 w/ 16GB and the TBD.


Today, at one point it shut off...I would remove and plug back in...it would stay dark.

Then I'd let it sit for 30seconds...try again... TBD would come one then drop.

Also late yesterday into today I'm starting to get the flicker. Now it's about every 20-30 seconds and eventually just goes all black. I'm not even using the display for the past few hours it was happening so much. I also disconencted the ethernet cable b/c I got tired of reconnecting my VPN/other connections over and over....


I guess I'm going to take it back b/c I run a bunch of local virtual machines and the 16GB of ram is what I need.


I just don't see how they will be able to patch this one... new firmware on the MB Pros that have 16GB of ram maybe...?


I'm assumign the normal cinema display will work better. I'll just not have the 1GB ethernet, and hub features...

Frustrating.

Dec 24, 2012 5:40 AM in response to clintonfrombirmingham

Trend is the non-retina MBP and the 8GB MBP retinas run just fine with the TBD that appear to be lemons to people with MPB Retina 16GB.


I would have taken it back already if the apple store wasn't 1.5hrs from me and it wasn't 12/23-24-25... yesterday I would've spent over an hour in mall traffic. 😟 Not fun.


I was there on the 23rd picking up a HHD recall on my 27" iMac, it had one of those segate drives that "will" die at some point. Took three days to swap a HHD. 😉 Had over an hour of mall traffic congestion. Still better than waiting on a shipment/RMA.


I'll be back after christmas and will try another TDB but from what I'm reading... some people were on their 2nd or 3rd with the retina 16GB rigs...and still having issues. I'm just debating wether to avoid the Thunderbolt display and go with the Cinema 27"...but that just irks the **** out of me b/c they cost the same and the TBD is made to work with this laptop almost exclusively.


I then compare the $999 to a $525(normally $699) Dell 29" panoramic ultrasharp. I do security work with tons of logs and statues...so the color acuracy isnt' as important as the real-estate/simplisity. We were trying to go from 2x20" to one single 27" with massive resolution. At this point I'm goign to have 2-3 days of debug in on this guy.


That's what I get for not searching the forums first... but who searches for issues on a monitor.... it's a bloody monitior.


I'll report back after Christmas how monitor #2 goes.

Jan 28, 2013 12:20 PM in response to docgoku

I've had my MBPro 13 inch for a while now and my 27 TBD for about 7 months (I think). It has been stable, then a few months back the TBD would shut off and not come back - no matter cycling display power, remove TB connector etc.


This became increasingly worse and performed a reset at boot up (per TBD manual) of Command, Option, P, R at startup. Now my display flickers constantly and is pretty useless.


What it *appears* to happen is the display believes the MB had its lid opened as the one USB drive I have connected to the display continues to spin and is accessible.

Jan 28, 2013 1:29 PM in response to docgoku

Everyone needs to understand that this is not (just) a Thunderbolt display problem. I think it is a problem on the computer end. I don't know if the port is at fault or the adapter. Since people with TBDs don't have an adapter, it must be the port.


All the symptions described here with the TBD happens with third party displays, using a TB to VGA adapter. I get the same video dropping and shimmering on three different displays.


I had the whole motherboard replaced by Apple (free) and have exactly the same problems on the replacement board.


It is time for Apple to grab the bull by the horns, admit the problem and get a fix going. This has gone on long enough.


😟

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New 27" Thunderbolt Display Flickers when attached to new 27" iMac

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