OSX Lion, Graphic Artifacts

i have the 2nd monitor too..... maybe is the HDMI/Thunderbolt adaptor???? all of u have a 2nd monitor connect to imac? or anyone have this issue without other monitor connected??mplease answer

I actually use MDP*-to-DVI adaptor, to which I connect my TV via HDMI-DVI cable (already had this cable from my old setup, so it was cheaper to just buy an MDP-to-DVI adaptor, instead of MDP-to-HDMI adaptor plus HDMI cable).

* - MDP is compatible with Thunderbolt port.

is that an original part? i'm using a commercial version of adaptator... but i start issue only with lion... with SL all work fine...

It's an original Apple adaptor, bought from a premium Apple reseller. And yeah, I doubt it has anything to do with having external displays connected.

"My workaround is to simply add a second monitor via the mini display/thunderbolt port. I am unable the reproduce the artifacts on the finder window when the second monitor is attached. The moment I disconnect the cable, the artifacts come back."

Graphic card output point . . . ?

mark u think is not depend by a type of adaptator is connected to imac?

Well, since the artifacts happen on both displays at the same time and all these adaptor thingies don't commmunicate back to the computer (they only recieve the information), they can't be the cause of the artifacts.

Correct - but what about the exits on the graphic card that feed those displays . . . ?

If it were the "exits", you wouldn't be able to see the artifacts on your screenshots.

Nor anything else . . . ?

Here is a video I recorded of my iMac going into a glitch with Mission Control. http://www.youtube.com/watch?v=5YMrU0xF_8c&feature=youtube_gdata_player

Same Issue on my 2 days new iMac. Happens in the menus bar, dock and dashboard.

3.4GHz i7, HD Radeon 6970 2gb

Looks like it might be 'back to support' the way my desktop is going again with sudden changes in pixel size and involuntary moves to either the top or right corners of the relevent page. FCPX started crashing now as well but thankfully it doesn't lose content when it does.

I've been experimenting the same problem for many days while trying everything to fix it till I literally couldn't turn on the Mac anymore, so the only thing it worked to me was re-installing Lion. No data lost in the process. And yep, it's an OpenGL problem.

Oh, btw:

I have had these graphic artifacts and was convinced that this was a Lion/AMD Radeon 6970M drivers issue, so I have been patiently waiting for a software update. I have reported the issue via the Apple feedback form. 3 or 4 days ago I thought that I had better phone Apple Care so that they would have a record there too. The assistant wanted me to do a PRAM/NVRAM reset, I was sceptical but complied. This seems to have worked for me - at least so far - I am still a little sceptical, as I am convinced that this is a drivers issue. I am not saying that it will work for all of you, but for me, so far, it seems to have worked.

Here are the exact steps that I performed:

1. Turned the power off at the socket.

2. Disconnected the power cord from the iMac.

3. Held the power button in on the iMac for 5 secs.

4. Reconnected the power cable and turned on power at the socket.

5. Turned on the iMac.

6. At the chime, held down COMMAND+OPTION+P+R. Keep holding.

7. Once the iMac chime's again let go of the keys and let the iMac start.

Not meaning to sound like I am teaching you to suck eggs with the instructions for the PRAM/NVRAM reset, I just wanted to give you the exact instructions that I followed :-)

I will let you know if the artifacts reappear at any point.