Your aggression is way too high. Try with aggression of 12 and increase it by 1 until you hit max hash rate.
It looks like your display driver crashed. You can try it with lower aggression and increase it like he said, and you can also adjust your core and mem clocks to different values. Alternatively you can also try higher or lower thread_concurrency values and see if they help -- every 7xxx card I've seen can do 18+ aggression if the core and memory clocks are set correctly along with thread_concurrency.
What do you suggest for thread_concurrency? If I set it much higher, cgminer just errors out:
[2013-03-12 10:52:07] Maximum buffer memory device 0 supports says 536870912
[2013-03-12 10:52:07] Your scrypt settings come to 1073741824
[2013-03-12 10:52:07] Error -61: clCreateBuffer (padbuffer8), decrease CT or in
crease LG
Just try the "--shaders" setting without the thread concurrency, you can't use both as they override each other. OR, if you are dead set on using a high concurrency (with cgminer), bump up the lookup gap by 1. You lose some performance but can use the high intensities also to make up a bit of that loss.
Also make sure you are up to date on cgminer, there have been a lot of changes made.
Edit : Try whatever your concurrency was above -32 and lookup gap +1. your setting is exactly 2x what your card would work with.
