Thunderbolt Display turns off randomly

OWC Larry, how do I ping you? I am having the TB blackout problem with OWC RAM and a Macbook Pro. I'd like to contact you about this... Thanks.

what did you reinstall, if I may ask? I'm having this problem with a Macbook Pro, so doesn't seem like there's anything to reinstall....

Its been working great after using the external thunderbolt cable from Apple., no issues for over a day..!

Ok i swapped out my ram for the orginal Samsung memory and I have not had a single flash all day. Not sure what to do at this point as 4GB is not enough for me and don't know wheere to get OEM apple memory cheap.

And you really don't want cheap RAM - PNY is perhaps the cheapest and the worst. OWC and Crucial both make excellent Mac RAM, OWC being a bit higher but tested more rigorously with Apple products,

Clinton

I have alsways used Crucial RAM and never had any issues.

This appears to be my problem as well. I have an MBA 2013 version connected to a new TBD. It worked ok for a few weeks then today started to go black randomly. I have a hard drive connected to a fire wire port (powered from the port) and an Ethernet connection. I tried removing the HD but no cjange, then I tried pulling out the ethernet and since then I have had no problems (30 minutes only - so early days yet).

When you consider that the bus runs at 10Gb/s and the ethernet data as well as everthing else has to be shoveled accross the link, it is not surprising that there can be noise or timing issues, expecially as the cables carrying this huge bandwidth are also basically cheap. When I was studying microwave engineering 25 years ago these data rates would have been considered totally amazing and only used in the realms of radar and satellite comms, I know I am getting old but as Scotty used to say, "Y' canna change the laws a' physics captain"

I just got my 27" TBD back from Apple and they replaced the cable then 3 hours later I got my blank screen... 😟 I disabled the GPU switching and unplugged my ethernet cable. Fingers crossed!

I re-inserted my ethernet connector after an hour without problems ( using a newer cable), and it seemed to be ok but I didn't run it for very long. I will replace the CAT-5 cable with a CAT-6 cable tomorrow and see what happens.

In most EU countries there is a 2 year warranty proscribed by law and apple must comply. Certainly in Germany you can get any apple product repaired within the 2 year period free of charge.

Maybe Denmark is the same.

See here: http://www.apple.com/legal/warranty/

I am in the US so here it's only 1 year and I bought it 1.5 years ago. I just paid $60 to replace the cable that did absolutely nothing. Also saw some threads about people replacing the memory? Did that work? I did that upgrade to my MBP awhile ago and have only seen these issues recently?

When you are working with really high frequency comms. then the system is usually well shielded (like a cable) and /or physically small (mobile phone). I suspect that the Thunderbolt interface is so fast and the system so big that the safety margins in a total Thunderbolt system are small. The errors in the whole serially connected system add up and when the total error is too great the system falls over. In a standard TBD / MBP oder MBA setup you have the motherboard in the computer which is well controlled, then the connector and cables (which are poorly controlled) and then the interior of the display and the interconnections there including the interface to the GBit Ethernet - which may or may not be well shielded - and then the further Thunderbolt daisy chain of connectors and cables.

The whole thing is like a satellite Link-Budget where small deteriorations in any of the components will cause failure of the whole system even though the component hasn't really become much worse at all and probably isn't always to blame! In this situation replacing the components is really a hit or miss affair. Probably the cables and conectors are always a good bet, but memory and ethernet peripherals could also be to blame.

This is really why no one has ever tried to do these bus speeds before with long cables and lots of interconnects , it is just very difficult to achieve in mass production at low cost.

We really don't see these issues with pure Thunderbolt products... and the certification and testing requirements don't even allow for any wiggle room when it comes to having a Thunderbolt product approved. The issues seem limited to displays and in the case of the Thunderbolt display, however the video is handed off such that it is with an external mini-Displayport to video cable and with the same kinds of issues.

I agree interference or a signal failure/degradtion or timing with the video chipset/memory/shared memory is already shown to be different factors with this OR it's actually noise from the Thunderbolt/video into the system that is the factor. A specific die rev of memory appears to be a factor (not necessary true cause / but subject to cause) in Mac mini systems. In multiple systems, Mac minis - MacBooks - iMacs, have seen issue resolved with the replacement of cheap MDP adapters in the case of non-thunderbolt displays...

Of course - when you have a Thunderbolt Display from Apple, with integrated cable - the situation is more difficult to remedy, especially if other things can adjust/control do not rememdy. In the case of MacBook Air and Retina models with this issue occuring, the only other factor to adjust would be what else is connected to the actual system of the Thunderbolt display.

With those thoughts shared.... I'd summarize / suggest - Thunderbolt itself isn't the issue here. The issue is manifesting with connected displays, the Thunderbolt display included (which at some point has a handoff from TB to the video output as noted above) - and as the issue with 3rd party DVI/HDMI displays has most often been resolved with a better/proper quality cable, very well may be a deficiency that Apple can resolve in a future Thunderbolt display design to fix the issue there as well. Either that - or it's a sensitivy in the video chipset.

As I continue to walk through this... can also note - significant improvements / reductions of this issue over the last 12 months have come from various Apple EFI and OS updates too. Perhaps more to come there too.

Sorry to say the flickering problem came back again 😟 - the Ethernet trick didn't work so my TBD is off to the great apple repairer in the sky to see if it can be saved.

I will be sure to send a link to this thread with it though as reference.

I did these three things and it has been working for the past 48 hours? Not sure if one of them or all threee together did the trick. Only been 2 days so I will report back if I get the blackout again!

Disable - Display - Auto djust bright

Disable - Energey Saver - Auto GPU switch

Unplug ethernet cable from back of TBD