iMac graphics screwing up

[A Macbook Pro]

This seems to happen when I watch a HD YouTube video on my 27'' 2011 iMac. What happens is the bottom half of the video gets yellow lines and flickers a bit. A refresh fixes it but once it happens my whole OS X graphics get screwed up. Here is a picture to show what I mean.

As far as I know only a restart fixes it. Doesn't seem to be occurring in Windows, only OS X Lion.

Any tips?

 

[s.horsfield]

Wirelessly posted (Mozilla/5.0 (iPod; U; CPU iPhone OS 4_3_5 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8L1 Safari/6533.18.5)

It's a Lion issue. No fixes as far as I know. Wait for apple to release a update (should be a few weeks time).

Sorry I couldn't be of more help

 

[A Macbook Pro]

Wirelessly posted (Mozilla/5.0 (iPod; U; CPU iPhone OS 4_3_5 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8L1 Safari/6533.18.5)

It's a Lion issue. No fixes as far as I know. Wait for apple to release a update (should be a few weeks time).

Sorry I couldn't be of more help

It's okay, I went on the Apple discussion forums and found another member with exactly the same issue. It's been pinpointed down to the 6970M with 2GB VRAM.

 

[AbeFroman77]

It's okay, I went on the Apple discussion forums and found another member with exactly the same issue. It's been pinpointed down to the 6970M with 2GB VRAM.

No, it's Lion. There's a 40+ page thread so far here:
https://discussions.apple.com/thread/3194165?start=0&tstart=0

There's freezing issues after resuming from sleep and artifacting.

 

[chrono1081]

+1 for Lion issue. My MBA did it last night and a restart fixed it. It never did it in Snow Leopard (well at first until the patch came out).

 

[leeds utd fc]

I'm also having similar problems with my 21.5 entry-level iMac. Stopping it from sleeping seems to have solved the problem - so far.