SMPFR

. Mine runs stable at 1900 memory without overvolting. Overvolting is the only thing that can actually damage your GPU so I wouldn't recommend it at all.

Then once you find the maximum memory clock speed, you need to find the sweet spot engine clock speed that matches it. It's a fine line where one more MHz will make the hashrate drop by 20%. It's somewhere in the .57 - 0.6 ratio range. Start your engine clock speed at half your memory clock speed and then increase it by 5 at a time. The hashrate should climb a little each rise in engine speed and then suddenly drop above a certain value. Decrease it by 1 then until you find it climbs dramatically. If your engine clock speed cannot get that high without crashing the GPU, you will have to use a lower memclock.

Then, and only then, bother trying to increase intensity further.

My final settings were:
--gpu-engine 1157 --gpu-memclock 1900 -I 20
for a hashrate of 725kH.

Note I did not bother setting a thread concurrency. Once you have the magic endpoint, look at what tc was chosen by the bin file generated and then hard code that in next time (eg --thread-concurrency 22336) as slight changes in thread concurrency will happen every time if you don't specify one, and the tc to clock ratios are critical!

Optimal thread concurrencies for 7xxx family:
7770: 8000 (200 kh/s, aggression 19)
7850: ????
7870: 15360 (400 kh/s, aggression 19)
7950: 21712 or 24000 (~575 kh/s)
7970 (cgminer): 22392 (~700 kh/s can be obtained with a core/memory ratio of 0.57)
7970 (reaper): 20992, 21712, or 24000 (~
7750: ????
7770: 8000 (200 kh/s, aggression 19)
7850: ????
7870: 15360 (400 kh/s, aggression 19)
7950: 21712 or 24000 (~575 kh/s)
7970 (cgminer): 22392 (~700 kh/s can be obtained with a core/memory ratio of 0.57) or 8192 (-g 2 -w 256 -I 13)
7970 (reaper): 20992, 21712, or 24000 (~650 kh/s can be obtained with reaper and core/memory ratio of 0.57, e.g. 900 MHz core and 1580 MHz memory. Over 725 KH/s can be achieved with memory overvolting.)