7970 Potential Issue?
 

So I just recently got a R7970 Lightning Edition and in Eyefinity it works just fine although occasionally the Windows Desktop Manager will freeze and restart. But the bigger problem is that when ever I play certain games in 1080p using one monitor, it will after sometime of game play the screen will freeze and lock up my computer. The screen looks like a bunch of vertical grey lines and my computer will not respond at all so I have to push the restart button on my computer case and when I restart Windows it won't give me the message that Windows has recovered from a unexpected shut down. Please help I have no idea if this is common with the 7970 or it's just AMD's drivers/bios? Thanks.

Possible culprits (other than a bad card):
1: GPU overheat. Monitor temps if you can at full load.
2: Not enough juice. What PSU do you have because an AX 850 should be able to handle a 7970 (shouldn't it?)?
3: MSAA. I have had huge problems with driver 12.4 when MSAA is enabled. Vertical blocks appear and it isn't pretty. 12.3 and 12.2 worked well with the MSAA.

Hope this helps, gl!

This sounds like a case of the card being unstable and needing an RMA.

The other, more remote possibility is the Motherboard is having issues. (Just ran into this one myself very recently.)