"I wanted you to know that I am having a horrible screen glitches after installing 10.7.2 on my mac pro. I have upgraded my mac pro over the years to keep it current. I have a Mac Pro 1.1. It is modified with new 5770 GPU, dual quad-core CPU's and 16 gb of ram.

I have included a link to a forum that talks about this very subject. I am sure that I am not the only one with this issue. (I've not read all posts in that thread, but ADC displays seem a common item in problem reports. (A DVI to ADC adapter used of course.)-Mike)
Please help spread the word, write about this problem. Hopefully we can get apple to listen!
https://discussions.apple.com/message/16333480#16333480
(Thread titled "My desktop screen keeps flashing".)
Thank you, John W."

Just before posting this, I checked that thread and here's a post from this morning with a tip/fix (which one other so far said also helped for his setup)

"So after a day of the flickering, and trying everything to solve it, I have fixed mine at least for now.

I took the monitor cable from the Apple DVI/ADC adaptor out my MacPRO while it is on, right out of the video card. Then I waited about 10 seconds and plugged it back into the video card.

Problem solved. I have not rebooted, no sleep mode and I have not logged out since doing this, so I do not know if this fixed it for good. (FYI: Some have noted this didn't survive a reboot/logout, etc)

So far it is back to it's good old self. Let me know if this works for anyone else.
Thanks, Jeff M."

The reply just below that from another affected owner said "Well that is just odd. That worked for me as well." (Maybe that forces a display re-detection?) Hopefully that helps others as well. (I was about to ask if the usual update TS tips were tried, zap pram/nvram, check for corrupted prefs/files, reinstall w/download updater, etc.)

But if anyone with a similar mac pro/video card (5770, 5870, 4870, etc) and -not- seen any problems in 10.7.2, send a note with details/specifics. Thanks.
(Please include info on any upgrades/addons installed, Display/Type (interface) used and for the record if you updated the bootrom/EFI. Just curious in regards to past posts on 2006 MacPros/QC CPUs/Lion and KPs - wondering if those with problems found 10.7.2 made any difference.)

Update: I've posted replies to this on a separate page of Feedback on OS X 10.7.2 on Early Mac Pros with Upgrades (CPUs/Video cards, etc).
Also - although Early (2006/2007) Mac Pro owners started this topic, I've since had a 2010 Mac Pro owner w/ATI 5870 card and adapted ADC display also report the same screen flashing problem in 10.7.2. And same (temporary) fix - disconnect/reconnect. He had a case open with apple and later wrote:

"Apple called me today to let me know that their engineers have reproduced the issue in-house on the 20" and 23" ADC LCD displays... and that it's been escalated, to be fixed in a future release"

"MacBook Pro (15-inch, Mid 2010): Intermittent black screen or loss of video
Apple has determined that a small number of MacBook Pro (15-inch, Mid 2010) computers may intermittently stop displaying video on the built-in display or on an external display connected to the MacBook Pro.

In this situation, you may also see a restart warning message (kernel panic?-Mike) before the video is lost or the display turns black or gray. Affected computers were manufactured between April 2010 and February 2011.

Apple is aware of the issue and is working on a solution. Keep your software up-to-date using Software Update."

Seeing that was a deja-vu moment, but hopefully it's not anything as widespread (or as major) as the (infamous) 8600M issues with some earlier models.
Update: As of 7/31/2012, the apple doc has been updated to note if the video software updates do not fix the problem that they will service affected models for 3 years from purchase date, which may be extended as needed. The emphasis/underline is mine, as wording is similar to the apple doc on 8600M issues that had several extensions over the years.)

"...Apple will service affected 15-inch MacBook Pro computers free of charge until three years from date of purchase. Apple will provide further extensions to this program as needed. This worldwide Apple program does not extend the standard warranty coverage of the affected MacBook Pro."

FYI: Friday's (Oct 14th) news has a reader's notes on this issue which he says happens regardless of the active GPU selected. And Oct. 26th news has notes from a reader that took his in for service. (Before apple posted an updater for SL users.)

Update from Apple: On Oct. 24th apple posted an update to (hopefully) address this:

"About MacBook Pro Video Update 1.0
This update addresses an issue where MacBook Pro (15-inch Mid 2010) computers may intermittently freeze or stop displaying video.
For detailed information about this update, please visit: https://support.apple.com/kb/TS4088.
(Updated doc from Oct 13th - MacBook Pro (15in, Mid 2010): Intermittent black screen or loss of video)

System Requirements: OS X Lion 10.7.2"
(FYI/Update: Apparently this is included in 10.7.3 as the apple doc on the issue no longer links to this update, instead saying to update to 10.7.3 or later.)

Update for Snow Leopard: On Nov 14th, 2011 Apple posted an updater for 10.6.8 users - see MacBook Pro Video Update 1.0 (Snow Leopard)
 

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