Apple Cinema Display MD 8149 Started Blinking

Echosyn

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Could be because it's 13 years old. 3 weeks ago the monitor screen started an occasional random blink that has become more frequent. Nothing in the adjacent environment has changed recently. The cable appears to be good. Video card? Gotta learn about that. Computer is G4 tower, Digital Audio, 733 MHz with Tiger. Any suggestions besides getting a up to date computer will be appreciated by this retiree on fixed income. For good measure I'll take the computer to the shop and clean it.
 
A few years ago - probably five - I had to replace the lamp unit in the back of my 17 inch "square" flat monitor. It was fairly easy DIY. It was a few years old at the time, and so maybe a similar age to your cinema display. I remember looking at a cinema display at the time, but decided to was too expensive at the time.

From memory, it flickered a bit and then went very dim. But then only one half "died". If all your screen has gone, then maybe it's not a light unit, as I can't imagine the cinema display having fewer lights than the 17 square. Maybe a power problem?

Can you see anything dimly if you shine a torch into the screen? If you can, then the video is there and it will more likely be a back light problem.
 
Wife just finished a grueling 6 hour stint working with email and she said the blinking increased in frequency as time passed and her eyes are sore from it. Increased operating time = increased heat accumulation. Dust retains heat. Gotta clean inside the computer. The monitor works very well other than the random blink. It responds properly to brightness up-down buttons at bottom right of monitor. In Sys. Pref. the refresh rate button is blurred and not accessible, so I can't change that. With monitor off I placed a flashlight, torch, against the screen and screen is pitch black. With monitor turned on and has white wallpaper all is normal and torch light does not penetrate beyond surface.
 
I think sgould was asking about the video image when the display acts up, and blinks off (losing the apparent video), and not just by shutting the power off.
If the blink is very short duration (just a flicker), then watching to see if the video image actually goes away - might not help you decide what is happening.
DO TRY reseating the video card in its slot. That would be easy to do if you are already cleaning dust, etc from the inside.
 
I'm just about to post a reply to my earlier thread about black screen on an iMac. A PRAM reset seems to have given a cure. At least for now. But we will see. Seems to be an Intel based problem and may not be relevant to yours.

This thread. http://macosx.com/forums/hardware-peripherals/322145-2011-27-inch-imac-black-screen-death.html

Do you have another computer that you can plug the screen into? A laptop or even someone else's computer. Or borrow a monitor to try on your machine. That could help to pin down whether you have a monitor or a computer problem.
 
The 8149 Cinema Display is an ADC connection, I think.
Echosyn would need another old Mac that also has an ADC port, if he wants to try the old monitor on a different Mac.

I also think it's a good idea to try another display, as you should also have a VGA connector on the video card.

Again, the display with ADC connector gets its power through the video card, in addition to the video signal, plus the USB ports, all through the same cable connector. That is the main reason to be sure to try reseating the graphics card in its slot.
 
No loss of image is apparent during the blink. We use 2 PowerPCs. The other is a G4 MDD with Leopard and a 20" Apple Cinema display. If cleaning and card reseating doesn't stop the flicker I'll try swapping the monitors. Thanks for the tips. I'll report back.
 
Question: What is/are the best circuit board cleaners for computers? I use clean pencil eraser on card contacts then wipe with dry Kleenex, but what cleaner is best for removing smog residue?
 
I would use isopropyl alcohol for general cleaning on circuit boards. I have a bottle of hi-test alcohol (91%), but I can't say that higher percent actually cleans better.
I don't usually see any need to use a contact cleaner of any kind. Card edge connectors would be self-cleaning, and I just unseat, reseat a couple of times, with a last firm push.
 
Thanks for the cleaning tips. It's cleaned, reinstalled and I'm replying through it. Graphics card contacts were tarnished and a new pencil eraser restored the bright gold finish. Will do the web work through this computer and if the blink reoccurs I'll swap monitors and see if it happens on the other computer. What do you suggest if it does that?
 
After cleaning the computer, video card and cable connectors then reinstalling with no strain on cables the blinking has stopped. Thank you guys for your gracious help. You will be blessed.
 
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