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CareyAnn

macrumors newbie
Original poster
Mar 10, 2011
3
0
Hello Forum!

I can't seem to find an answer anywhere for my latest headache ;)

Quick sum-up: My HD 30" Cinema Display has developed some graphic disturbance over the last month and it gets worse and better throughout the day. It seems to only happen in the dark areas of the screen. I have a Mac Pro 1.1 and a Mac Pro 2 and both computers display the same problem. I have brought the monitor into a local Apple Service provider only to get a clean bill of health. $79 later I am back at home and the problem is still here. I took a Video as well as a Screen Shot so you can see my issue and see it is not my video card.

Does anyone know if there is a compatibility issue with my Display and newer Hardware or video cards?

Both my Macs display perfectly fine on my other Dell LCD monitor FYI.

Help! :confused:

Video:


Screen Shot:
Screenshot2011-03-10at45727PM.png
 
Other information I just realized might be helpful. Both computers have been updated to Snow Leopard and both Video Cards have been upgraded to ATI Radeon HD 5770.
 
Are the 5770s you're using flashed PC cards or genuine Apple cards? Either way, try it out with your original cards and see if it still occurs. Also, are you using any DVI extension cables?

The reason I ask is because this looks similar to an effect I once had on my 30" ACD when using a flashed card and a DVI extension cable. Basically if I extended it at all, I got similar artifacts to yours - only in the dark areas. I didn't get it without the extension cable. I also don't think I got it with my original 7300 GT. I got the feeling that different video cards supply a different 'strength' signal over the DVI cables. While digital signals shouldn't degrade anything like analogue signals, a dual link monitor is pushing the limits of DVI as it is and signal degradation can occur.

I'm not saying that's what's happening here but it's something to rule out. If using your original graphics cards doesn't help then I'm afraid it looks like your screen's on it's way out in which case I really feel for you. :(
 
Hi Spanky ;)...yes both cards are original Apple cards :apple: and work perfectly well on my Dell monitor. I have no extension cables either for my Cinema Display. When I picked up my monitor today from the tech shop I noticed they were using a Mac Pro with an older card inside (I noticed because the tower was open) and they could not replicate my problem. My monitor worked perfectly well for them (they had it on all day).

Seems the compatibility issue lies between my Mac Pro (ATI 5770) & the HD Monitor.

I am hoping wishing there is a driver update or some other miracle cure.
 
Edit: Sorry! Thought it was reflected in the screen shot.

But yeah, looks like a bad cable, or bad display hardware.
 
30" Apple Cinema Display

I am experiencing the same problem as you are and even worse than what you have posted. I have had my whole set up parked at an Apple center for almost 6 weeks only to be told that there may be a compatibility issue with the old acd (mine being about 4 yrs old) and the new ATI Radeon HD 5770. Well, the people at the Genius bar "seem" to think and I believe they are not 100% sure of this diagnosis. The same as you, am asking for help.
 
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