Yeah, anyone using 2.11.3 please chime, mostly people are saying that either the program doesn't run or the kernel throws lots of invalids so I'm a little skeptical.
I've been playing a bit with cgminer (2.11.2 and 2.11.3) and scrypt during the last few hours.
So far the best performance I could achieve on my GV-R797OC-3GD on windows 7 x64 with catalyst 13.2b7 was around 720kH/s with the following settings:
cgminer.exe --scrypt -o http://xxx -u x -p x --intensity 13 -g 2 --thread-concurrency 8192 --lookup-gap 2 --gpu-engine 1044 --gpu-memclock 1500
a more conservative 620kH/s with
cgminer.exe --scrypt -o http://xxx -u x -p x --intensity 13 -g 2 --thread-concurrency 8192 --lookup-gap 2 --gpu-engine 900 --gpu-memclock 1155
and an even more conservative 550kH/s with
cgminer.exe --scrypt -o http://xxx -u x -p x --intensity 13 -g 2 --thread-concurrency 8192 --lookup-gap 2 --gpu-engine 800 --gpu-memclock 870
Increasing thread concurrency above 8192 with --lookup-gap 2 always returns an error like
Maximum buffer memory device 0 supports says 536870912
Your scrypt settings come to 1467482112
Error -61: clCreateBuffer (padbuffer8), decrease CT or increase LG
Lowering thread concurrency below 8192 always produces hardware errors.
With -g > 1 using any intensity higher or lower than 13 will result in lower hashrates.
With -g 1 higher than 13 intensities will more or less match -g 2 -I 13 hashrate at the expenses of system responsiveness.
Increasing lookup gap allows for higher thread concurrencies, but it won't improve performance.
Setting the correct core/memory ratio for your card is the most important tweak, even a small 10MHz difference can make you lose/gain 100-200kH/s.