A small sugestion. Try 1125/leave memory at default. I figured at 7950/7950, at my cards, its usually the memory that makes issues when its lowered, not the gpu increased - chrome used to crush on me same way.
I just discovered something after installing the 13.2 beta5 drivers. I was checking if I could watch youtube videos while hashing, on my overclocked card. Apparently I can't, because it crashed my video driver. However since I restarted bfgminer after the crash, I have been consistently running 5-10mh/s faster.
I'm running at 1125/1125 with stock volts. Before I was averaging just under 670mh/s. Now I'm averaging just under 680mh/s. Edit: Also, the temps are 5 degrees C lower!
I'll have to run it for a while before I can be sure that it's really hashing faster, and not just displaying a higher value, but I wonder if anyone else has had something similar happen.
Edit: a couple of things I should mention:
1.) I had been, for a couple of months using 12.10 drivers. During that time, I found 1125 to be about the fastest I can run stable. It gets about 670mh/s consistently at that speed.
2.) I upgraded to 13.2 beta5 earlier today and observed little or no increase in mh/s. Still around 670mh/s.
3.) Since the crash, when I try to play a Youtube video I just get a green square, even after restarting firefox. This makes me think it's some driver subsystem that crashed and didn't restart, freeing up more resources for mining.
4.) Curiously, GPU-Z shows the GPU workload at 0-2%. It is definitely hashing however, as I've kept an eye on my pool's stats for the last 15min and seen the hashrate for that worker stay steady.